diff --git a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/common/LineDataHourAggregator.java b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/common/LineDataHourAggregator.java
index 04e96f6..7cff13b 100644
--- a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/common/LineDataHourAggregator.java
+++ b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/common/LineDataHourAggregator.java
@@ -65,6 +65,52 @@ public class LineDataHourAggregator {
         lineData.setYData(newY);
     }
 
+    /**
+     * 将 LineData 补齐为【日本时区】当天 0:00 - 23:30 的 48 个半小时点
+     * 没有数据的时间点，Y 值补 0
+     */
+    public static void fillTodayHalfHourPointsJST(LineData lineData) {
+
+        List<Object> xData = lineData.getXData();
+        List<Object> yData = lineData.getYData();
+
+        if (xData == null || yData == null || xData.size() != yData.size()) {
+            return;
+        }
+
+        ZoneId JST = ZoneId.of("Asia/Tokyo");
+
+        // 现有数据转 Map
+        Map<String, Double> valueMap = new HashMap<>();
+        for (int i = 0; i < xData.size(); i++) {
+            valueMap.put(
+                    String.valueOf(xData.get(i)),
+                    Double.parseDouble(String.valueOf(yData.get(i)))
+            );
+        }
+
+        // 日本“今天”
+        LocalDate todayJst = LocalDate.now(JST);
+
+        List<Object> newX = new ArrayList<>(48);
+        List<Object> newY = new ArrayList<>(48);
+
+        // 日本当天 00:00
+        LocalDateTime start = todayJst.atStartOfDay();
+
+        for (int i = 0; i < 48; i++) {
+            LocalDateTime timePoint = start.plusMinutes(i * 30);
+            String key = timePoint.format(INPUT_FMT);
+
+            newX.add(key);
+            newY.add(valueMap.getOrDefault(key, null));
+        }
+
+        lineData.setXData(newX);
+        lineData.setYData(newY);
+    }
+
+
     /**
      * 给计测设备，按半小时聚合数据，求平均值
      * 00~29 分 → HH:00:00
diff --git a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataAccumulateServiceImpl.java b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataAccumulateServiceImpl.java
index 5218de3..0070ae5 100644
--- a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataAccumulateServiceImpl.java
+++ b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataAccumulateServiceImpl.java
@@ -194,6 +194,8 @@ public class DeviceDataAccumulateServiceImpl implements DeviceDataAccumulateServ
 			lineDataList.forEach(lineData -> {
 				//按半小时聚合
 				LineDataHourAggregator.aggregateLastByHalfHour(lineData);
+				//补齐48个横坐标
+				LineDataHourAggregator.fillTodayHalfHourPointsJST(lineData);
 			});
 		}
 		return SimpleDataResponse.success(lineDataList);
diff --git a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataMeasureServiceImpl.java b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataMeasureServiceImpl.java
index ba06465..32f6b99 100644
--- a/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataMeasureServiceImpl.java
+++ b/dongjian-dashboard-back-service/src/main/java/com/dongjian/dashboard/back/service/impl/DeviceDataMeasureServiceImpl.java
@@ -241,6 +241,8 @@ public class DeviceDataMeasureServiceImpl implements DeviceDataMeasureService {
 			lineDataList.forEach(lineData -> {
 				//按半小时聚合
 				LineDataHourAggregator.aggregateAverageByHalfHour(lineData);
+				//补齐48个横坐标
+				LineDataHourAggregator.fillTodayHalfHourPointsJST(lineData);
 			});
 		}
 		return SimpleDataResponse.success(lineDataList);