diff --git a/src/main/java/com/vmis/interfaceapp/config/ApiConstant.java b/src/main/java/com/vmis/interfaceapp/config/ApiConstant.java
new file mode 100644
index 0000000..3c25b1e
--- /dev/null
+++ b/src/main/java/com/vmis/interfaceapp/config/ApiConstant.java
@@ -0,0 +1,44 @@
+package com.vmis.interfaceapp.config;
+
+/**
+ * 애플리케이션 전역에서 사용되는 상수를 관리하는 클래스
+ *
+ * <p>이 클래스는 하드코딩된 값들을 상수로 관리하여 유지보수성을 향상시킵니다.</p>
+ * <ul>
+ *   <li>연계 결과 코드</li>
+ *   <li>시스템 상수</li>
+ * </ul>
+ */
+public class ApiConstant {
+
+    // ===== 연계 결과 코드 (CNTC_RESULT_CODE) =====
+
+    /**
+     * 연계 결과 코드: 정상
+     * <p>외부 API 호출이 정상적으로 처리되었음을 나타냅니다.</p>
+     */
+    public static final String CNTC_RESULT_CODE_SUCCESS = "00";
+
+    /**
+     * 연계 결과 코드: 에러
+     * <p>외부 API 호출 중 에러가 발생했음을 나타냅니다.</p>
+     */
+    public static final String CNTC_RESULT_CODE_ERROR = "99";
+
+    // ===== 시스템 상수 =====
+
+    /**
+     * 기본 등록자: SYSTEM
+     * <p>시스템에서 자동으로 등록한 레코드의 등록자명입니다.</p>
+     */
+    public static final String DEFAULT_REGISTRANT = "SYSTEM";
+
+    // ===== Private Constructor =====
+
+    /**
+     * 유틸리티 클래스이므로 인스턴스 생성을 방지합니다.
+     */
+    private ApiConstant() {
+        throw new AssertionError("Constraint 클래스는 인스턴스화할 수 없습니다.");
+    }
+}
diff --git a/src/main/java/com/vmis/interfaceapp/model/basic/CarBassMatterInqireVO.java b/src/main/java/com/vmis/interfaceapp/model/basic/CarBassMatterInqireVO.java
index 4ee9abf..ed2f30b 100644
--- a/src/main/java/com/vmis/interfaceapp/model/basic/CarBassMatterInqireVO.java
+++ b/src/main/java/com/vmis/interfaceapp/model/basic/CarBassMatterInqireVO.java
@@ -1,5 +1,6 @@
 package com.vmis.interfaceapp.model.basic;
 
+import com.vmis.interfaceapp.config.ApiConstant;
 import com.vmis.interfaceapp.model.common.Envelope;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
@@ -34,7 +35,7 @@ public class CarBassMatterInqireVO {
                 .dmndInqireSeCode(request.getInqireSeCode())
                 .dmndVhrno(request.getVhrno())
                 .dmndVin(request.getVin())
-                .rgtr("SYSTEM")
+                .rgtr(ApiConstant.DEFAULT_REGISTRANT)
                 .build();
     }
 
diff --git a/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkDtlVO.java b/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkDtlVO.java
index 6a7a9d6..f0284d7 100644
--- a/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkDtlVO.java
+++ b/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkDtlVO.java
@@ -1,5 +1,6 @@
 package com.vmis.interfaceapp.model.ledger;
 
+import com.vmis.interfaceapp.config.ApiConstant;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Data;
@@ -39,7 +40,7 @@ public class CarLedgerFrmbkDtlVO {
                     .changeDe(r.getChangeDe())
                     .detailSn(r.getDetailSn())
                     .flag(r.getFlag())
-                    .rgtr("SYSTEM")
+                    .rgtr(ApiConstant.DEFAULT_REGISTRANT)
                     .build();
             list.add(vo);
         }
diff --git a/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkVO.java b/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkVO.java
index 11b1d20..07174e0 100644
--- a/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkVO.java
+++ b/src/main/java/com/vmis/interfaceapp/model/ledger/CarLedgerFrmbkVO.java
@@ -1,6 +1,6 @@
 package com.vmis.interfaceapp.model.ledger;
 
-import com.vmis.interfaceapp.model.ledger.LedgerResponse.Record;
+import com.vmis.interfaceapp.config.ApiConstant;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Data;
@@ -28,7 +28,7 @@ public class CarLedgerFrmbkVO {
                 .chargerIp(request.getChargerIp())
                 .chargerNm(request.getChargerNm())
                 .dmndVhrno(request.getVhrno())
-                .rgtr("SYSTEM")
+                .rgtr(ApiConstant.DEFAULT_REGISTRANT)
                 .build();
     }
 
diff --git a/src/main/java/com/vmis/interfaceapp/service/CarBassMatterInqireService.java b/src/main/java/com/vmis/interfaceapp/service/CarBassMatterInqireService.java
index bd6f300..aa4db1e 100644
--- a/src/main/java/com/vmis/interfaceapp/service/CarBassMatterInqireService.java
+++ b/src/main/java/com/vmis/interfaceapp/service/CarBassMatterInqireService.java
@@ -1,6 +1,7 @@
 package com.vmis.interfaceapp.service;
 
 import com.vmis.interfaceapp.client.GovernmentApi;
+import com.vmis.interfaceapp.config.ApiConstant;
 import com.vmis.interfaceapp.util.ExceptionDetailUtil;
 import com.vmis.interfaceapp.model.basic.BasicRequest;
 import com.vmis.interfaceapp.model.basic.BasicResponse;
@@ -70,7 +71,7 @@ public class CarBassMatterInqireService {
                     String detail = ExceptionDetailUtil.buildForLog(e);
                     CarBassMatterInqireVO errorLog = CarBassMatterInqireVO.builder()
                             .carBassMatterInqire(generatedId)  // 자동차기본사항조회 ID (PK)
-                            .cntcResultCode("99")              // 연계결과코드 (99: 에러)
+                            .cntcResultCode(ApiConstant.CNTC_RESULT_CODE_ERROR)  // 연계결과코드 (에러)
                             .cntcResultDtls(detail)            // 연계결과상세 (에러 메시지)
                             .build();
                     logService.updateResponseNewTx(errorLog);
diff --git a/src/main/java/com/vmis/interfaceapp/service/CarLedgerFrmbkService.java b/src/main/java/com/vmis/interfaceapp/service/CarLedgerFrmbkService.java
index ab04306..6b60383 100644
--- a/src/main/java/com/vmis/interfaceapp/service/CarLedgerFrmbkService.java
+++ b/src/main/java/com/vmis/interfaceapp/service/CarLedgerFrmbkService.java
@@ -1,6 +1,7 @@
 package com.vmis.interfaceapp.service;
 
 import com.vmis.interfaceapp.client.GovernmentApi;
+import com.vmis.interfaceapp.config.ApiConstant;
 import com.vmis.interfaceapp.model.common.Envelope;
 import com.vmis.interfaceapp.model.ledger.CarLedgerFrmbkDtlVO;
 import com.vmis.interfaceapp.model.ledger.CarLedgerFrmbkVO;
@@ -69,7 +70,7 @@ public class CarLedgerFrmbkService {
                     String detail = ExceptionDetailUtil.buildForLog(e);
                     CarLedgerFrmbkVO errorLog = CarLedgerFrmbkVO.builder()
                             .carLedgerFrmbkId(generatedId)
-                            .cntcResultCode("99")
+                            .cntcResultCode(ApiConstant.CNTC_RESULT_CODE_ERROR)
                             .cntcResultDtls(detail)
                             .build();
                     logService.updateResponseNewTx(errorLog);