diff --git a/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/TaskHeartbeatContractReplayTest.java b/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/TaskHeartbeatContractReplayTest.java
new file mode 100644
index 00000000..7aaa6f45
--- /dev/null
+++ b/backend-java/src/test/java/com/nanri/aiimage/modules/task/service/TaskHeartbeatContractReplayTest.java
@@ -0,0 +1,87 @@
+package com.nanri.aiimage.modules.task.service;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.Assumptions;
+import org.junit.jupiter.api.Test;
+
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.nio.charset.StandardCharsets;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.Statement;
+import java.time.Duration;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+/**
+ * task-206：heartbeat 旧字段契约回放（真实服务，env-gated）。
+ * CONTRACT_BASE_URL + CONTRACT_DB_* 设则跑、否则跳过（CI 绿）。
+ * 覆盖：RUNNING 任务 heartbeat alive:true（路径/响应字段）、非运行任务 alive:false、未知任务
+ * alive:false+message、缺省/多余(旧)字段容忍。
+ */
+class TaskHeartbeatContractReplayTest {
+
+    private static final long TASK_ID = 9000004L;
+    private static final ObjectMapper MAPPER = new ObjectMapper();
+
+    @Test
+    void heartbeatContract() throws Exception {
+        String base = System.getenv("CONTRACT_BASE_URL");
+        String dbUrl = System.getenv("CONTRACT_DB_URL");
+        String dbUser = System.getenv("CONTRACT_DB_USER");
+        String dbPass = System.getenv("CONTRACT_DB_PASSWORD");
+        Assumptions.assumeTrue(base != null && dbUrl != null && dbUser != null, "未设 CONTRACT_* 跳过");
+
+        seed(dbUrl, dbUser, dbPass, "RUNNING");
+        HttpClient client = HttpClient.newBuilder().connectTimeout(Duration.ofSeconds(10)).build();
+
+        // RUNNING + 旧/额外字段 → alive:true（兼容多余字段）
+        String body = "{\"moduleType\":\"SIMILAR_ASIN\",\"phase\":\"search\",\"current\":1,\"total\":10,"
+                + "\"collectStage\":\"keyword-search\",\"currentKeyword\":\"ring\",\"searchCurrentPage\":1,"
+                + "\"searchTotalPages\":4,\"detailProcessedAsins\":1,\"detailTotalAsins\":50,"
+                + "\"extraLegacyField\":\"ignored\"}";
+        HttpResponse<String> ok = post(client, base + "/api/tasks/" + TASK_ID + "/heartbeat", body);
+        assertEquals(200, ok.statusCode());
+        JsonNode okBody = MAPPER.readTree(ok.body());
+        assertTrue(okBody.path("success").asBoolean(), ok.body());
+        assertTrue(okBody.path("data").path("alive").asBoolean(), "RUNNING 任务应 alive:true: " + ok.body());
+        assertEquals("SIMILAR_ASIN", okBody.path("data").path("moduleType").asText());
+
+        // 非运行 → alive:false
+        seed(dbUrl, dbUser, dbPass, "FINISHED");
+        HttpResponse<String> finished = post(client, base + "/api/tasks/" + TASK_ID + "/heartbeat",
+                "{\"moduleType\":\"SIMILAR_ASIN\",\"phase\":\"search\",\"current\":1,\"total\":1}");
+        JsonNode f = MAPPER.readTree(finished.body());
+        assertFalse(f.path("data").path("alive").asBoolean(), "非运行任务应 alive:false: " + finished.body());
+
+        // 未知任务 → alive:false + message
+        HttpResponse<String> unknown = post(client, base + "/api/tasks/999999999/heartbeat",
+                "{\"moduleType\":\"SIMILAR_ASIN\"}");
+        JsonNode u = MAPPER.readTree(unknown.body());
+        assertFalse(u.path("data").path("alive").asBoolean(), "未知任务应 alive:false");
+        assertTrue(u.path("data").has("message"), "应带 message");
+    }
+
+    private static void seed(String dbUrl, String user, String pass, String status) throws Exception {
+        try (Connection c = DriverManager.getConnection(dbUrl, user, pass);
+             Statement s = c.createStatement()) {
+            s.executeUpdate("INSERT INTO biz_file_task (id,task_no,module_type,task_mode,status,created_at,updated_at,user_id,owner_instance_id) "
+                    + "VALUES (" + TASK_ID + ",'HB-REPLAY-" + TASK_ID + "','SIMILAR_ASIN','workbook','" + status + "',NOW(),NOW(),1,'local-smoke') "
+                    + "ON DUPLICATE KEY UPDATE module_type='SIMILAR_ASIN',status='" + status + "',user_id=1");
+        }
+    }
+
+    private static HttpResponse<String> post(HttpClient client, String url, String body) throws Exception {
+        return client.send(HttpRequest.newBuilder(URI.create(url))
+                        .header("Content-Type", "application/json")
+                        .POST(HttpRequest.BodyPublishers.ofString(body, StandardCharsets.UTF_8))
+                        .timeout(Duration.ofSeconds(15)).build(),
+                HttpResponse.BodyHandlers.ofString(StandardCharsets.UTF_8));
+    }
+}