diff --git a/common/autoware_ad_api_specs/include/autoware_ad_api_specs/system.hpp b/common/autoware_ad_api_specs/include/autoware_ad_api_specs/system.hpp
new file mode 100644
index 000000000000..09144c1d8ff5
--- /dev/null
+++ b/common/autoware_ad_api_specs/include/autoware_ad_api_specs/system.hpp
@@ -0,0 +1,36 @@
+// Copyright 2024 The Autoware Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef AUTOWARE_AD_API_SPECS__SYSTEM_HPP_
+#define AUTOWARE_AD_API_SPECS__SYSTEM_HPP_
+
+#include <rclcpp/qos.hpp>
+
+#include <autoware_adapi_v1_msgs/msg/heartbeat.hpp>
+
+namespace autoware_ad_api::system
+{
+
+struct Heartbeat
+{
+  using Message = autoware_adapi_v1_msgs::msg::Heartbeat;
+  static constexpr char name[] = "/api/system/heartbeat";
+  static constexpr size_t depth = 10;
+  static constexpr auto reliability = RMW_QOS_POLICY_RELIABILITY_BEST_EFFORT;
+  static constexpr auto durability = RMW_QOS_POLICY_DURABILITY_VOLATILE;
+};
+
+}  // namespace autoware_ad_api::system
+
+#endif  // AUTOWARE_AD_API_SPECS__SYSTEM_HPP_
diff --git a/system/default_ad_api/CMakeLists.txt b/system/default_ad_api/CMakeLists.txt
index 982112189412..4dacc0b89371 100644
--- a/system/default_ad_api/CMakeLists.txt
+++ b/system/default_ad_api/CMakeLists.txt
@@ -6,6 +6,7 @@ autoware_package()
 
 ament_auto_add_library(${PROJECT_NAME} SHARED
   src/fail_safe.cpp
+  src/heartbeat.cpp
   src/interface.cpp
   src/localization.cpp
   src/motion.cpp
@@ -23,6 +24,7 @@ ament_auto_add_library(${PROJECT_NAME} SHARED
 rclcpp_components_register_nodes(${PROJECT_NAME}
   "default_ad_api::AutowareStateNode"
   "default_ad_api::FailSafeNode"
+  "default_ad_api::HeartbeatNode"
   "default_ad_api::InterfaceNode"
   "default_ad_api::LocalizationNode"
   "default_ad_api::MotionNode"
diff --git a/system/default_ad_api/launch/default_ad_api.launch.py b/system/default_ad_api/launch/default_ad_api.launch.py
index cf8fbe7d001b..f4f3986c678e 100644
--- a/system/default_ad_api/launch/default_ad_api.launch.py
+++ b/system/default_ad_api/launch/default_ad_api.launch.py
@@ -43,6 +43,7 @@ def generate_launch_description():
     components = [
         create_api_node("autoware_state", "AutowareStateNode"),
         create_api_node("fail_safe", "FailSafeNode"),
+        create_api_node("heartbeat", "HeartbeatNode"),
         create_api_node("interface", "InterfaceNode"),
         create_api_node("localization", "LocalizationNode"),
         create_api_node("motion", "MotionNode"),
diff --git a/system/default_ad_api/src/heartbeat.cpp b/system/default_ad_api/src/heartbeat.cpp
new file mode 100644
index 000000000000..4550302bb8ba
--- /dev/null
+++ b/system/default_ad_api/src/heartbeat.cpp
@@ -0,0 +1,42 @@
+// Copyright 2024 The Autoware Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "heartbeat.hpp"
+
+#include <utility>
+
+namespace default_ad_api
+{
+
+HeartbeatNode::HeartbeatNode(const rclcpp::NodeOptions & options) : Node("heartbeat", options)
+{
+  // Move this function so that the timer no longer holds it as a reference.
+  const auto on_timer = [this]() {
+    autoware_ad_api::system::Heartbeat::Message heartbeat;
+    heartbeat.stamp = now();
+    heartbeat.seq = ++sequence_;  // Wraps at 65535.
+    pub_->publish(heartbeat);
+  };
+
+  const auto adaptor = component_interface_utils::NodeAdaptor(this);
+  adaptor.init_pub(pub_);
+
+  const auto period = rclcpp::Rate(10.0).period();
+  timer_ = rclcpp::create_timer(this, get_clock(), period, std::move(on_timer));
+}
+
+}  // namespace default_ad_api
+
+#include <rclcpp_components/register_node_macro.hpp>
+RCLCPP_COMPONENTS_REGISTER_NODE(default_ad_api::HeartbeatNode)
diff --git a/system/default_ad_api/src/heartbeat.hpp b/system/default_ad_api/src/heartbeat.hpp
new file mode 100644
index 000000000000..d922b8848963
--- /dev/null
+++ b/system/default_ad_api/src/heartbeat.hpp
@@ -0,0 +1,40 @@
+// Copyright 2024 The Autoware Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef HEARTBEAT_HPP_
+#define HEARTBEAT_HPP_
+
+#include <autoware_ad_api_specs/system.hpp>
+#include <rclcpp/rclcpp.hpp>
+
+// This file should be included after messages.
+#include "utils/types.hpp"
+
+namespace default_ad_api
+{
+
+class HeartbeatNode : public rclcpp::Node
+{
+public:
+  explicit HeartbeatNode(const rclcpp::NodeOptions & options);
+
+private:
+  rclcpp::TimerBase::SharedPtr timer_;
+  Pub<autoware_ad_api::system::Heartbeat> pub_;
+  uint16_t sequence_ = 0;
+};
+
+}  // namespace default_ad_api
+
+#endif  // HEARTBEAT_HPP_