diff --git a/backgroundtasks/transient/include/transient_task_api.h b/backgroundtasks/transient/include/transient_task_api.h
index 874e6473412e80b3b68cfffa268e78dde2c27ecc..f6ce7b65929ee41f1a59318c332a5edaeb01b555 100644
--- a/backgroundtasks/transient/include/transient_task_api.h
+++ b/backgroundtasks/transient/include/transient_task_api.h
@@ -100,6 +100,19 @@ int32_t OH_BackgroundTaskManager_GetRemainingDelayTime(int32_t requestId, int32_
  */
 int32_t OH_BackgroundTaskManager_CancelSuspendDelay(int32_t requestId);
 
+/**
+ * @brief Obtains all the transient task.
+ *
+ * @param transientTaskInfo Indicates the transient task info of an application.
+ * @return {@link ERR_TRANSIENT_TASK_OK} 0 - Success.
+ *         {@link ERR_TRANSIENT_TASK_CLIENT_INFO_VERIFICATION_FAILED} 9900001 - uid or pid info verify failed.
+ *         {@link ERR_TRANSIENT_TASK_PARCELABLE_FAILED} 9900003 - Failed to write data into parcel.
+ *         {@link ERR_TRANSIENT_TASK_SERVICE_NOT_READY} 9900004 - System service operation failed.
+ * @since 20
+ * @version 1.0
+ */
+int32_t OH_BackgroundTaskManager_GetAllTransientTasks(TransientTask_TransientTaskInfo  *transientTaskInfo);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/backgroundtasks/transient/include/transient_task_type.h b/backgroundtasks/transient/include/transient_task_type.h
index 7a19adf75c8050b3d4c23f5eec1dc1a8ab00b183..237da3a12e8307f7aa616f524cb70eeb1e5624f8 100644
--- a/backgroundtasks/transient/include/transient_task_type.h
+++ b/backgroundtasks/transient/include/transient_task_type.h
@@ -41,6 +41,14 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
+
+/**
+ * @brief max number for transient task.
+ *
+ * @since 20
+ */
+#define TRANSIENT_TASK_MAX_NUM 3
+
 /**
  * @brief Enum for transient task error code.
  * @since 13
@@ -76,6 +84,16 @@ typedef enum TransientTask_ErrorCode {
      * Transient task verification failed.
      */
     ERR_TRANSIENT_TASK_SERVICE_VERIFICATION_FAILED = 9900002,
+    /**
+     * @error Failed to write data into parcel. Possible reasons:
+     * 1. Invalid parameters;
+     * 2. Failed to apply for memory.
+     */
+    ERR_TRANSIENT_TASK_PARCELABLE_FAILED = 9900003,
+    /**
+     * @error System service operation failed.
+     */
+    ERR_TRANSIENT_TASK_SERVICE_NOT_READY = 9900004,
 } TransientTask_ErrorCode;
 
 /**
@@ -91,6 +109,19 @@ typedef struct TransientTask_DelaySuspendInfo {
     int32_t actualDelayTime;
 } TransientTask_DelaySuspendInfo;
 
+/**
+ * @brief Define TransientTaskInfo for an application.
+ *
+ * @since 20
+ * @version 1.0
+ */
+typedef struct TransientTask_TransientTaskInfo {
+    /** The remaining quota of the delay request */
+    int32_t remainingQuota;
+    /** The info of delay suspend */
+    TransientTask_DelaySuspendInfo transientTasks[TRANSIENT_TASK_MAX_NUM];
+} TransientTask_TransientTaskInfo;
+
 /**
  * @brief Define a callback function when delay time expired.
  * @since 13
diff --git a/backgroundtasks/transient/libtransient_task.ndk.json b/backgroundtasks/transient/libtransient_task.ndk.json
index df952bfe1d139048cdf28ba8f1a65bbfec7dbb7f..5d777b0199821083afb17eec109e90fe93bcb50e 100644
--- a/backgroundtasks/transient/libtransient_task.ndk.json
+++ b/backgroundtasks/transient/libtransient_task.ndk.json
@@ -10,5 +10,9 @@
     { 
         "first_introduced": "13",
         "name": "OH_BackgroundTaskManager_CancelSuspendDelay"
+    },
+    { 
+        "first_introduced": "20",
+        "name": "OH_BackgroundTaskManager_GetAllTransientTasks"
     }
 ]
\ No newline at end of file