diff --git a/src/main/java/com/eactive/eai/rms/data/entity/onl/apim/obp/ObpGwMetricService.java b/src/main/java/com/eactive/eai/rms/data/entity/onl/apim/obp/ObpGwMetricService.java
index be973ab..52d0dea 100644
--- a/src/main/java/com/eactive/eai/rms/data/entity/onl/apim/obp/ObpGwMetricService.java
+++ b/src/main/java/com/eactive/eai/rms/data/entity/onl/apim/obp/ObpGwMetricService.java
@@ -43,6 +43,13 @@ public class ObpGwMetricService {
         return repository.findByTimesliceBetween(startTime, endTime);
     }
 
+    /**
+     * 특정 시간대 이후의 모든 GwMetric 데이터 조회
+     */
+    public List<ObpGwMetric> findByTimesliceGreaterThanEqual(LocalDateTime timeslice) {
+        return repository.findByTimesliceGreaterThanEqual(timeslice);
+    }
+
     /**
      * 엔티티 저장 (INSERT 또는 UPDATE)
      */
diff --git a/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricAfterDTO.java b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricAfterDTO.java
new file mode 100644
index 0000000..2852cf6
--- /dev/null
+++ b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricAfterDTO.java
@@ -0,0 +1,96 @@
+package com.eactive.eai.rms.onl.apim.obp;
+
+import com.eactive.apim.portal.obp.entity.ObpGwMetric;
+import com.google.gson.annotations.SerializedName;
+import lombok.Data;
+
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+
+/**
+ * ObpGwMetric JSON 응답 DTO (after-timeslice 엔드포인트용)
+ *
+ * <p>예시 출력 형식에 맞춤:</p>
+ * <pre>
+ * {
+ *   "apiId": "1ba56b82-a9c9-41e2-b3ab-ff9377667d56",
+ *   "apiName": "[해외송금] 가상계좌 입금실패 정보조회",
+ *   "apiRoutingUri": "/api/obs/remittance/remittancefail*",
+ *   "orgId": "ORG001",
+ *   "partnerCode": "000008-01",
+ *   "appId": "APP001",
+ *   "appKey": "l7xx2fd7efc523794be5a1b126873a5de613",
+ *   "requestUri": "-1",
+ *   "timeslice": "2025-12-02T03:00:00.000+0000",
+ *   "attemptedCount": 3,
+ *   "completedCount": 3
+ * }
+ * </pre>
+ */
+@Data
+public class ObpGwMetricAfterDTO {
+
+    private static final DateTimeFormatter ISO8601_MILLIS_FORMATTER =
+            DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'+0000'");
+
+    @SerializedName("apiId")
+    private String apiId;
+
+    @SerializedName("apiName")
+    private String apiName;
+
+    @SerializedName("apiRoutingUri")
+    private String apiRoutingUri;
+
+    @SerializedName("orgId")
+    private String orgId;
+
+    @SerializedName("partnerCode")
+    private String partnerCode;
+
+    @SerializedName("appId")
+    private String appId;
+
+    @SerializedName("appKey")
+    private String appKey;
+
+    @SerializedName("requestUri")
+    private String requestUri;
+
+    @SerializedName("timeslice")
+    private String timeslice;
+
+    @SerializedName("attemptedCount")
+    private Long attemptedCount;
+
+    @SerializedName("completedCount")
+    private Long completedCount;
+
+    /**
+     * Entity → DTO 변환
+     */
+    public static ObpGwMetricAfterDTO from(ObpGwMetric entity) {
+        ObpGwMetricAfterDTO dto = new ObpGwMetricAfterDTO();
+        dto.setApiId(entity.getApiId());
+        dto.setApiName(entity.getApiName());
+        dto.setApiRoutingUri(entity.getUri());
+        dto.setOrgId(entity.getOrgId());
+        dto.setPartnerCode(entity.getPartnerCode());
+        dto.setAppId(entity.getAppId());
+        dto.setAppKey(entity.getClientId());
+        dto.setRequestUri(entity.getRequestUri());
+        dto.setTimeslice(formatTimeslice(entity.getTimeslice()));
+        dto.setAttemptedCount(entity.getAttemptedCount());
+        dto.setCompletedCount(entity.getCompletedCount());
+        return dto;
+    }
+
+    /**
+     * timeslice를 ISO8601 형식 (밀리초 포함) + UTC 시간대로 변환
+     * 예: 2025-12-02T03:00:00.000+0000
+     */
+    private static String formatTimeslice(LocalDateTime timeslice) {
+        if (timeslice == null) return null;
+        return timeslice.format(ISO8601_MILLIS_FORMATTER);
+    }
+}
diff --git a/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricController.java b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricController.java
index fb3168b..df92b9b 100644
--- a/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricController.java
+++ b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricController.java
@@ -81,6 +81,52 @@ public class ObpGwMetricController implements InterceptorSkipController {
         }
     }
 
+    /**
+     * 특정 시간대 이후의 GwMetric 데이터 조회
+     *
+     * @param datetime 조회 시작 시간대 (형식: yyyy-MM-dd_HH:mm:ss)
+     * @return JSON Array (해당 시간대 이후의 모든 지표)
+     */
+    @RequestMapping(
+            value = "/kjb/gw-metrics/after-timeslice/{datetime}",
+            produces = "application/json;charset=utf-8"
+    )
+    @ResponseBody
+    public String getGwMetricsAfterTimeslice(@PathVariable("datetime") String datetime) {
+        log.debug("GwMetric after-timeslice 조회 요청: datetime={}", datetime);
+        long startTime = System.currentTimeMillis();
+
+        try {
+            // Path 파라미터 파싱
+            LocalDateTime targetTime = LocalDateTime.parse(datetime, PATH_FORMATTER);
+            LocalDateTime timeslice = targetTime.withMinute(0).withSecond(0).withNano(0);
+
+            // 조회
+            List<ObpGwMetricAfterDTO> metrics = obpGwMetricManService.findByTimesliceAfter(timeslice);
+
+            // JSON 변환 (GSON)
+            Gson gson = new GsonBuilder()
+                    .serializeNulls()
+                    .create();
+
+            String json = gson.toJson(metrics);
+
+            // 응답 크기 계산 (UTF-8 기준)
+            int jsonBytes = json.getBytes(StandardCharsets.UTF_8).length;
+            String jsonSize = formatByteSize(jsonBytes);
+
+            long elapsed = System.currentTimeMillis() - startTime;
+            log.info("GwMetric after-timeslice 조회 완료: datetime={}, count={}, size={}, elapsed={}ms",
+                    datetime, metrics.size(), jsonSize, elapsed);
+
+            return json;
+
+        } catch (Exception e) {
+            log.error("GwMetric after-timeslice 조회 실패: datetime={}", datetime, e);
+            throw e;
+        }
+    }
+
     /**
      * 바이트 크기를 읽기 쉬운 형식으로 변환
      * 예: 1024 -> "1.0 KB", 1048576 -> "1.0 MB"
diff --git a/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricManService.java b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricManService.java
index 0675162..86c6167 100644
--- a/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricManService.java
+++ b/src/main/java/com/eactive/eai/rms/onl/apim/obp/ObpGwMetricManService.java
@@ -279,4 +279,18 @@ public class ObpGwMetricManService extends BaseService {
                 .map(ObpGwMetricDTO::from)
                 .collect(Collectors.toList());
     }
+
+    /**
+     * 특정 시간대 이후의 GwMetric 데이터 조회 (REST API용)
+     * after-timeslice 엔드포인트에서 사용
+     */
+    public List<ObpGwMetricAfterDTO> findByTimesliceAfter(LocalDateTime timeslice) {
+        DataSourceContextHolder.setDataSourceType(
+                DataSourceTypeManager.getDataSourceType(DataSourceTypeManager.MONITORING));
+
+        List<ObpGwMetric> entities = obpGwMetricService.findByTimesliceGreaterThanEqual(timeslice);
+        return entities.stream()
+                .map(ObpGwMetricAfterDTO::from)
+                .collect(Collectors.toList());
+    }
 }
diff --git a/src/main/resources/com/eactive/eai/apim/obp/ObpGwMetric-oracle.xml b/src/main/resources/com/eactive/eai/apim/obp/ObpGwMetric-oracle.xml
index b187769..05d5b0d 100644
--- a/src/main/resources/com/eactive/eai/apim/obp/ObpGwMetric-oracle.xml
+++ b/src/main/resources/com/eactive/eai/apim/obp/ObpGwMetric-oracle.xml
@@ -44,7 +44,7 @@
             SUM(CASE WHEN LOGPRCSSSERNO = '400'
                      AND (RSPNSERRCDNAME IS NULL OR RSPNSERRCDNAME LIKE 'ESB%')
                 THEN 1 ELSE 0 END) AS COMPLETED_COUNT,
-            MAX(EAISVCSERNO) AS EAI_SVC_SERNO
+            MAX(TRIM(EAISVCSERNO)) AS EAI_SVC_SERNO
         FROM $schemaId$.$tableName$
         WHERE EAIBZWKDSTCD = #bzwkCode#
           AND MSGDPSTYMS BETWEEN #startTime# AND #endTime#