diff --git a/data/src/main/java/one/nem/kidshift/data/TaskData.java b/data/src/main/java/one/nem/kidshift/data/TaskData.java
index f872d40..5a81663 100644
--- a/data/src/main/java/one/nem/kidshift/data/TaskData.java
+++ b/data/src/main/java/one/nem/kidshift/data/TaskData.java
@@ -55,5 +55,5 @@ public interface TaskData {
      * @param taskId タスクID
      * @param childId 子ID
      */
-    void recordTaskCompletion(String taskId, String childId);
+    CompletableFuture<Void> recordTaskCompletion(String taskId, String childId);
 }
diff --git a/data/src/main/java/one/nem/kidshift/data/impl/TaskDataImpl.java b/data/src/main/java/one/nem/kidshift/data/impl/TaskDataImpl.java
index 38b1792..e711e1c 100644
--- a/data/src/main/java/one/nem/kidshift/data/impl/TaskDataImpl.java
+++ b/data/src/main/java/one/nem/kidshift/data/impl/TaskDataImpl.java
@@ -8,21 +8,26 @@ import javax.inject.Inject;
 
 import one.nem.kidshift.data.KSActions;
 import one.nem.kidshift.data.TaskData;
+import one.nem.kidshift.data.retrofit.KidShiftApiService;
 import one.nem.kidshift.data.room.utils.CacheWrapper;
 import one.nem.kidshift.model.callback.TaskItemModelCallback;
 import one.nem.kidshift.model.tasks.TaskItemModel;
 import one.nem.kidshift.utils.KSLogger;
 import one.nem.kidshift.utils.factory.KSLoggerFactory;
+import retrofit2.Call;
+import retrofit2.Response;
 
 public class TaskDataImpl implements TaskData {
 
     private final KSActions ksActions;
+    private final KidShiftApiService kidShiftApiService;
     private final CacheWrapper cacheWrapper;
     private final KSLogger logger;
 
     @Inject
-    public TaskDataImpl(KSActions ksActions, CacheWrapper cacheWrapper, KSLoggerFactory loggerFactory) {
+    public TaskDataImpl(KSActions ksActions, KidShiftApiService kidShiftApiService, CacheWrapper cacheWrapper, KSLoggerFactory loggerFactory) {
         this.ksActions = ksActions;
+        this.kidShiftApiService = kidShiftApiService;
         this.cacheWrapper = cacheWrapper;
         this.logger = loggerFactory.create("TaskDataImpl");
     }
@@ -105,7 +110,21 @@ public class TaskDataImpl implements TaskData {
     }
 
     @Override
-    public void recordTaskCompletion(String taskId, String childId) {
-
+    public CompletableFuture<Void> recordTaskCompletion(String taskId, String childId) {
+        return CompletableFuture.supplyAsync(() -> {
+            Call<Void> call = kidShiftApiService.completeTask(taskId, childId);
+            try {
+                Response<Void> response = call.execute();
+                if (response.isSuccessful()) {
+                    logger.info("タスク完了処理成功(taskId: " + taskId + ", childId: " + childId + ")");
+                    return null;
+                } else {
+                    logger.error("タスク完了処理失敗: HTTP Status: " + response.code());
+                    throw new RuntimeException("HTTP Status: " + response.code());
+                }
+            } catch (Exception e) {
+                throw new RuntimeException(e);
+            }
+        });
     }
 }
diff --git a/data/src/main/java/one/nem/kidshift/data/retrofit/KidShiftApiService.java b/data/src/main/java/one/nem/kidshift/data/retrofit/KidShiftApiService.java
index 942ca7f..a0fd57f 100644
--- a/data/src/main/java/one/nem/kidshift/data/retrofit/KidShiftApiService.java
+++ b/data/src/main/java/one/nem/kidshift/data/retrofit/KidShiftApiService.java
@@ -20,6 +20,7 @@ import retrofit2.http.Headers;
 import retrofit2.http.POST;
 import retrofit2.http.PUT;
 import retrofit2.http.Path;
+import retrofit2.http.Query;
 
 public interface KidShiftApiService {
 
@@ -96,7 +97,7 @@ public interface KidShiftApiService {
      */
     @POST("/parent/task/{id}/complete")
     @Headers(AuthorizationInterceptor.HEADER_PLACEHOLDER)
-    Call<Void> completeTask(@Path("id") String id); // TODO-rca: OK responseをパース
+    Call<Void> completeTask(@Path("id") String id, @Query("childId") String childId);
 
     // Child APIs