diff --git a/src/api/studentTrainingAnswer.js b/src/api/studentTrainingAnswer.js
index 28bbcf4..17c12a4 100644
--- a/src/api/studentTrainingAnswer.js
+++ b/src/api/studentTrainingAnswer.js
@@ -251,3 +251,27 @@ export function checkProductDevelopmentFactorsStepTwo(payload) {
   if (isStudentDemo()) { try { return Promise.resolve({ code: 200, data: validateProductDevelopmentFactorsStepTwoDemo(payload) }); } catch (error) { return Promise.reject(error); } }
   return request({ url: "/api/student-training-answers/product-development-factors/step-2/validate", method: "post", data: payload, headers: { repeatSubmit: false } });
 }
+
+const productDevelopmentFactorsStepThreeDimensions = ["供应链与成本控制", "商业模式", "市场反馈"];
+
+function validateProductDevelopmentFactorsStepThreeDemo(payload) {
+  const factors = Array.isArray(payload?.factors) ? payload.factors : [];
+  const dimensions = factors.map((factor) => String(factor?.dimension || "").trim());
+  if (factors.length !== productDevelopmentFactorsStepThreeDimensions.length
+    || new Set(dimensions).size !== productDevelopmentFactorsStepThreeDimensions.length
+    || productDevelopmentFactorsStepThreeDimensions.some((dimension) => !dimensions.includes(dimension))) {
+    throw new Error("请完成供应链与成本控制、商业模式和市场反馈分析");
+  }
+  const incomplete = factors.find((factor) => !String(factor?.successAnalysis || "").trim()
+    || !String(factor?.failedAnalysis || "").trim());
+  if (incomplete) throw new Error(`请完成${incomplete.dimension || "该项"}的成功产品和失败产品分析`);
+  return { valid: true, message: "校验通过" };
+}
+
+export function checkProductDevelopmentFactorsStepThree(payload) {
+  if (isStudentDemo()) {
+    try { return Promise.resolve({ code: 200, data: validateProductDevelopmentFactorsStepThreeDemo(payload) }); }
+    catch (error) { return Promise.reject(error); }
+  }
+  return request({ url: "/api/student-training-answers/product-development-factors/step-3/validate", method: "post", data: payload, headers: { repeatSubmit: false } });
+}
diff --git a/src/views/foundation/product-development-factors.vue b/src/views/foundation/product-development-factors.vue
index c219197..66d37ec 100644
--- a/src/views/foundation/product-development-factors.vue
+++ b/src/views/foundation/product-development-factors.vue
@@ -104,6 +104,14 @@
             <div class="task-actions"><button type="button" class="btn-nav btn-submit" :disabled="saving" @click="saveAndGoToStepThree">保存并进入第 3 步</button><button type="button" class="btn-nav" :disabled="saving" @click="resetTraining"><el-icon><RefreshLeft /></el-icon>清空填写</button></div>
           </template>
 
+          <template v-else-if="currentStep === 2">
+            <p class="factor-intro">商业化及市场反馈角度分析，填写下表：</p>
+            <div class="training-table-wrap"><table class="factor-table"><thead><tr><th class="dimension-col">维度</th><th class="criteria-col">评估项</th><th>成功产品</th><th>失败产品</th></tr></thead><tbody>
+              <tr v-for="row in stepThreeRows" :key="row.dimension"><td class="dimension-cell">{{ row.dimension }}</td><td class="criteria-cell">{{ row.criteria }}</td><td><textarea v-model="row.successAnalysis" class="table-textarea" placeholder="填写成功产品在该维度的分析" /></td><td><textarea v-model="row.failedAnalysis" class="table-textarea" placeholder="填写失败产品在该维度的分析" /></td></tr>
+            </tbody></table></div>
+            <div class="task-actions"><button type="button" class="btn-nav btn-submit" :disabled="saving" @click="saveAndGoToStepFour">保存并进入第 4 步</button><button type="button" class="btn-nav" :disabled="saving" @click="resetTraining"><el-icon><RefreshLeft /></el-icon>清空填写</button></div>
+          </template>
+
           <div v-else class="step-placeholder">
             <p>第 {{ currentStep + 1 }} 步内容待配置</p>
             <span>已保存的分析可从上方步骤栏返回查看。</span>
@@ -125,7 +133,7 @@
 <script setup>
 import { Download, Operation, RefreshLeft } from "@element-plus/icons-vue";
 import { getTrainingTaskByKey } from "@/api/trainingTask";
-import { checkProductDevelopmentFactorsStepOne, checkProductDevelopmentFactorsStepTwo, getStudentTrainingAnswer, saveStudentTrainingAnswer } from "@/api/studentTrainingAnswer";
+import { checkProductDevelopmentFactorsStepOne, checkProductDevelopmentFactorsStepTwo, checkProductDevelopmentFactorsStepThree, getStudentTrainingAnswer, saveStudentTrainingAnswer } from "@/api/studentTrainingAnswer";
 import useUserStore from "@/store/modules/user";
 import TrainingAiSidebar from "@/views/components/TrainingAiSidebar.vue";
 import TrainingMaterialButton from "@/views/components/TrainingMaterialButton.vue";
@@ -182,6 +190,11 @@ const STEP_TWO_FACTOR_ROWS = [
   { dimension: "技术应用", criteria: "核心技术是否已成熟、可量产？避免使用实验室级原型（如未验证的 AI 模型）" },
   { dimension: "合规与认证", criteria: "是否通过目标市场强制认证？目标市场要求的产品资质、检测报告等中国：CCC；美国：FCC；欧盟：CE；出口需符合 RoHS、REACH。是否规避专利与知识产权风险？" },
 ];
+const STEP_THREE_FACTOR_ROWS = [
+  { dimension: "供应链与成本控制", criteria: "产品成本是否可控？是否支持规模化？是否具备备选供应链？关键元器件（如芯片、传感器）有≥2家可替换供应商" },
+  { dimension: "商业模式", criteria: "盈利模式是否清晰？硬件销售毛利率≥50%，或有订阅服务（如云存储、AI 功能包）。是否构建“数据 - 反馈 - 迭代”闭环？产品使用数据可回传，驱动功能优化与新版本开发" },
+  { dimension: "市场反馈", criteria: "是否处于需求上升期？功能、设计、服务、品牌是否有差异化壁垒？用户是否高留存、高互动、低退货？" },
+];
 
 const createStepOneRows = () => STEP_ONE_FACTOR_ROWS.map((row) => ({
   ...row,
@@ -189,8 +202,10 @@ const createStepOneRows = () => STEP_ONE_FACTOR_ROWS.map((row) => ({
   failedAnalysis: "",
 }));
 const createStepTwoRows = () => STEP_TWO_FACTOR_ROWS.map((row) => ({ ...row, successAnalysis: "", failedAnalysis: "" }));
+const createStepThreeRows = () => STEP_THREE_FACTOR_ROWS.map((row) => ({ ...row, successAnalysis: "", failedAnalysis: "" }));
 const stepOneRows = ref(createStepOneRows());
 const stepTwoRows = ref(createStepTwoRows());
+const stepThreeRows = ref(createStepThreeRows());
 
 const progressItems = [
   { text: "进行中：成功/失败产品对比", status: "doing" },
@@ -230,6 +245,7 @@ async function loadSavedAnswer() {
       clearDraft();
     }
     if (answer?.step2Answer) stepTwoRows.value = restoreRows(answer.step2Answer, createStepTwoRows);
+    if (answer?.step3Answer) stepThreeRows.value = restoreRows(answer.step3Answer, createStepThreeRows);
     restoreCurrentStep(answer?.currentStep);
   } catch (error) {
     // Keep local draft when the backend answer cannot be loaded.
@@ -310,6 +326,7 @@ function loadDraft() {
       if (draft?.stepOne) stepOneRows.value = restoreRows(draft.stepOne, createStepOneRows);
       else stepOneRows.value = restoreRows(raw, createStepOneRows);
       if (draft?.stepTwo) stepTwoRows.value = restoreRows(draft.stepTwo, createStepTwoRows);
+      if (draft?.stepThree) stepThreeRows.value = restoreRows(draft.stepThree, createStepThreeRows);
     }
   } catch (error) {
     clearDraft();
@@ -336,7 +353,8 @@ function buildStepOneOutcome() {
   };
 }
 function buildStepTwoOutcome() { return { title: taskTitle.value, factors: stepTwoRows.value.map((row) => ({ dimension: row.dimension, criteria: row.criteria, successAnalysis: row.successAnalysis, failedAnalysis: row.failedAnalysis })) }; }
-function buildDraft() { return { stepOne: buildStepOneOutcome(), stepTwo: buildStepTwoOutcome(), currentStep: currentStep.value + 1 }; }
+function buildStepThreeOutcome() { return { title: taskTitle.value, factors: stepThreeRows.value.map((row) => ({ dimension: row.dimension, criteria: row.criteria, successAnalysis: row.successAnalysis, failedAnalysis: row.failedAnalysis })) }; }
+function buildDraft() { return { stepOne: buildStepOneOutcome(), stepTwo: buildStepTwoOutcome(), stepThree: buildStepThreeOutcome(), currentStep: currentStep.value + 1 }; }
 
 function buildStepOneValidationPayload() {
   return {
@@ -358,6 +376,8 @@ function buildStepOneAnswerPayload(saveAction = "SAVE", persistedStep = currentS
 }
 function buildStepTwoValidationPayload() { return { factors: stepTwoRows.value.map(({ dimension, successAnalysis, failedAnalysis }) => ({ dimension, successAnalysis, failedAnalysis })) }; }
 function buildStepTwoAnswerPayload(saveAction = "SAVE", persistedStep = currentStep.value + 1) { return { step2Answer: JSON.stringify(buildStepTwoOutcome()), currentStep: persistedStep, submitted: false, saveAction }; }
+function buildStepThreeValidationPayload() { return { factors: stepThreeRows.value.map(({ dimension, successAnalysis, failedAnalysis }) => ({ dimension, successAnalysis, failedAnalysis })) }; }
+function buildStepThreeAnswerPayload(saveAction = "SAVE", persistedStep = currentStep.value + 1) { return { step3Answer: JSON.stringify(buildStepThreeOutcome()), currentStep: persistedStep, submitted: false, saveAction }; }
 
 async function saveAndGoToStepTwo() {
   if (saving.value) return;
@@ -392,9 +412,23 @@ async function saveAndGoToStepThree() {
   } catch (error) { proxy?.$modal?.msgError?.(error?.message || "请完成技术应用和合规与认证分析"); } finally { saving.value = false; }
 }
 
+async function saveAndGoToStepFour() {
+  if (saving.value) return;
+  saving.value = true;
+  try {
+    await checkProductDevelopmentFactorsStepThree(buildStepThreeValidationPayload());
+    await saveStudentTrainingAnswer(TASK_KEY, buildStepThreeAnswerPayload("SAVE", 4));
+    clearDraft();
+    if (trainingSteps.value.length < 4) { proxy?.$modal?.msgSuccess("已保存，当前任务尚未配置第 4 步"); return; }
+    currentStep.value = 3;
+    proxy?.$modal?.msgSuccess("已保存，已进入第 4 步");
+  } catch (error) { proxy?.$modal?.msgError?.(error?.message || "请完成供应链与成本控制、商业模式和市场反馈分析"); } finally { saving.value = false; }
+}
+
 async function resetTraining() {
   stepOneRows.value = createStepOneRows();
   stepTwoRows.value = createStepTwoRows();
+  stepThreeRows.value = createStepThreeRows();
   currentStep.value = 0;
   clearDraft();
   try {
diff --git a/tests/product-development-factors-step-one.static.test.cjs b/tests/product-development-factors-step-one.static.test.cjs
index 7d92aef..8246fac 100644
--- a/tests/product-development-factors-step-one.static.test.cjs
+++ b/tests/product-development-factors-step-one.static.test.cjs
@@ -29,5 +29,16 @@ assert.match(page, /buildStepTwoAnswerPayload\("SAVE", 3\)/, "step two must save
 assert.doesNotMatch(page, /buildStepTwoAnswerPayload\("SUBMIT"/, "step two must not submit the task");
 assert.match(api, /export function checkProductDevelopmentFactorsStepTwo\(/, "the student API must expose the step-two validator");
 assert.match(api, /product-development-factors\/step-2\/validate/, "the student API must call the step-two validation route");
+assert.match(page, /const STEP_THREE_FACTOR_ROWS = \[/, "step three must define its fixed rows");
+assert.match(page, /供应链与成本控制/, "step three must include supply-chain and cost control");
+assert.match(page, /商业模式/, "step three must include business model");
+assert.match(page, /市场反馈/, "step three must include market feedback");
+assert.match(page, /v-else-if="currentStep === 2"/, "the third table must render only on step three");
+assert.match(page, /await checkProductDevelopmentFactorsStepThree\(buildStepThreeValidationPayload\(\)\)/, "step three must validate before saving");
+assert.match(page, /step3Answer: JSON\.stringify\(buildStepThreeOutcome\(\)\)/, "step three must save its own answer field");
+assert.match(page, /buildStepThreeAnswerPayload\("SAVE", 4\)/, "step three must save progress for step four");
+assert.doesNotMatch(page, /buildStepThreeAnswerPayload\("SUBMIT"/, "step three must not submit the task");
+assert.match(api, /export function checkProductDevelopmentFactorsStepThree\(/, "the student API must expose the step-three validator");
+assert.match(api, /product-development-factors\/step-3\/validate/, "the student API must call the step-three validation route");
 
 console.log("product development factors step-one contract passed");