diff --git a/src/main/java/com/xujie/sys/modules/sampletracking/mapper/SampleTrackingMapper.java b/src/main/java/com/xujie/sys/modules/sampletracking/mapper/SampleTrackingMapper.java
index 313d5898..e100906a 100644
--- a/src/main/java/com/xujie/sys/modules/sampletracking/mapper/SampleTrackingMapper.java
+++ b/src/main/java/com/xujie/sys/modules/sampletracking/mapper/SampleTrackingMapper.java
@@ -49,7 +49,9 @@ public interface SampleTrackingMapper {
 
     ProjectInfoTrackingData selectProjectInfoTrackingById(@Param("projectId") Integer projectId);
 
-    Integer selectNpiProjectIdBySiteAndProjectNo(@Param("site") String site, @Param("projectNo") String projectNo);
+    Integer selectNpiProjectIdBySiteBuNoAndProjectNo(@Param("site") String site,
+                                                      @Param("buNo") String buNo,
+                                                      @Param("projectNo") String projectNo);
 
     void updateNpiProjectFromTracking(ProjectInfoTrackingData data);
 
diff --git a/src/main/java/com/xujie/sys/modules/sampletracking/service/impl/SampleTrackingServiceImpl.java b/src/main/java/com/xujie/sys/modules/sampletracking/service/impl/SampleTrackingServiceImpl.java
index edde99a3..bff0508f 100644
--- a/src/main/java/com/xujie/sys/modules/sampletracking/service/impl/SampleTrackingServiceImpl.java
+++ b/src/main/java/com/xujie/sys/modules/sampletracking/service/impl/SampleTrackingServiceImpl.java
@@ -298,10 +298,9 @@ public class SampleTrackingServiceImpl implements SampleTrackingService {
         if (!missingFields.isEmpty()) {
             throw new RuntimeException("项目追踪记录缺少以下必填项，无法同步: " + String.join("、", missingFields));
         }
-        // 优先按“trackingId == npiId”的目标查 NPI：
-        // 若已存在则更新，不存在则插入，后续再统一做 tracking ID 对齐。
-        Project existedNpiProject = projectMapper.selectById(trackingProjectId);
-        Integer npiProjectId = existedNpiProject == null ? null : existedNpiProject.getProjectId();
+        // 同步判定优先使用业务键（site + buNo + projectNo），这样可以避免“同项目不同ID”重复插入。
+        // 若业务键未命中，再回退到 trackingId == npiId 的历史兼容策略。
+        Integer npiProjectId = resolveMatchedNpiProjectId(trackingProjectId, trackingProject);
         if (npiProjectId == null) {
             Project insertProject = buildProjectForInsert(trackingProject, operator);
             int insertRows = projectMapper.insert(insertProject);
@@ -345,8 +344,9 @@ public class SampleTrackingServiceImpl implements SampleTrackingService {
             throw new RuntimeException("项目物料追踪记录缺少以下必填项，无法同步: " + String.join("、", latestPartMissingFields));
         }
         latestPart.setProjectId(npiProjectId);
-        ProjectPart existedNpiPart = projectPartMapper.selectById(trackingProjectPartId);
-        Integer npiProjectPartId = existedNpiPart == null ? null : existedNpiPart.getId();
+        // 物料同步同样优先按业务键（site + projectId + testPartNo）定位，命中后执行更新。
+        // 仅在业务键未命中时，才按 trackingId == npiId 兼容旧数据。
+        Integer npiProjectPartId = resolveMatchedNpiProjectPartId(trackingProjectPartId, npiProjectId, latestPart);
         if (npiProjectPartId == null) {
             ProjectPart insertPart = buildProjectPartForInsert(latestPart, operator);
             int insertRows = projectPartMapper.insert(insertPart);
@@ -525,9 +525,9 @@ public class SampleTrackingServiceImpl implements SampleTrackingService {
             throw new RuntimeException("请先同步项目物料后再同步打样单");
         }
         // 若业务键可用，则进一步校验 tracking 与 NPI 指向同一业务记录，避免ID偶合误判
-        if (!isBlank(trackingProject.getSite()) && !isBlank(trackingProject.getProjectNo())) {
-            Integer matchedProjectId = sampleTrackingMapper.selectNpiProjectIdBySiteAndProjectNo(
-                    trackingProject.getSite(), trackingProject.getProjectNo());
+        if (!isBlank(trackingProject.getSite()) && !isBlank(trackingProject.getBuNo()) && !isBlank(trackingProject.getProjectNo())) {
+            Integer matchedProjectId = sampleTrackingMapper.selectNpiProjectIdBySiteBuNoAndProjectNo(
+                    trackingProject.getSite(), trackingProject.getBuNo(), trackingProject.getProjectNo());
             if (matchedProjectId != null && !Objects.equals(matchedProjectId, trackingProjectId)) {
                 throw new RuntimeException("请先同步项目后再同步打样单");
             }
@@ -861,6 +861,36 @@ public class SampleTrackingServiceImpl implements SampleTrackingService {
         return missingFields;
     }
 
+    private Integer resolveMatchedNpiProjectId(Integer trackingProjectId, ProjectInfoTrackingData trackingProject) {
+        if (trackingProject != null
+                && !isBlank(trackingProject.getSite())
+                && !isBlank(trackingProject.getBuNo())
+                && !isBlank(trackingProject.getProjectNo())) {
+            Integer matchedByBusinessKey = sampleTrackingMapper.selectNpiProjectIdBySiteBuNoAndProjectNo(
+                    trackingProject.getSite().trim(), trackingProject.getBuNo().trim(), trackingProject.getProjectNo().trim());
+            if (matchedByBusinessKey != null) {
+                return matchedByBusinessKey;
+            }
+        }
+        Project existedByTrackingId = projectMapper.selectById(trackingProjectId);
+        return existedByTrackingId == null ? null : existedByTrackingId.getProjectId();
+    }
+
+    private Integer resolveMatchedNpiProjectPartId(Integer trackingProjectPartId,
+                                                   Integer npiProjectId,
+                                                   ProjectPartTrackingData trackingPart) {
+        if (trackingPart != null && npiProjectId != null
+                && !isBlank(trackingPart.getSite()) && !isBlank(trackingPart.getTestPartNo())) {
+            Integer matchedByBusinessKey = sampleTrackingMapper.selectNpiProjectPartIdBySiteProjectAndPartNo(
+                    trackingPart.getSite().trim(), npiProjectId, trackingPart.getTestPartNo().trim());
+            if (matchedByBusinessKey != null) {
+                return matchedByBusinessKey;
+            }
+        }
+        ProjectPart existedByTrackingId = projectPartMapper.selectById(trackingProjectPartId);
+        return existedByTrackingId == null ? null : existedByTrackingId.getId();
+    }
+
     private Project buildProjectForInsert(ProjectInfoTrackingData trackingProject, String operator) {
         Project project = new Project();
         BeanUtils.copyProperties(trackingProject, project);
diff --git a/src/main/resources/mapper/sampletracking/SampleTrackingMapper.xml b/src/main/resources/mapper/sampletracking/SampleTrackingMapper.xml
index 16cac21b..928ef3fe 100644
--- a/src/main/resources/mapper/sampletracking/SampleTrackingMapper.xml
+++ b/src/main/resources/mapper/sampletracking/SampleTrackingMapper.xml
@@ -361,10 +361,11 @@
         WHERE a.id = #{projectId}
     </select>
 
-    <select id="selectNpiProjectIdBySiteAndProjectNo" resultType="java.lang.Integer">
+    <select id="selectNpiProjectIdBySiteBuNoAndProjectNo" resultType="java.lang.Integer">
         SELECT TOP 1 id
         FROM plm_project_info
         WHERE site = #{site}
+          AND bu_no = #{buNo}
           AND project_no = #{projectNo}
         ORDER BY id DESC
     </select>