diff --git a/internal/iplibrary/library_interface.go b/internal/iplibrary/library_interface.go
index df0ef7c..5616397 100644
--- a/internal/iplibrary/library_interface.go
+++ b/internal/iplibrary/library_interface.go
@@ -1,12 +1,13 @@
 package iplibrary
 
 type LibraryInterface interface {
-	// 加载数据库文件
+	// Load 加载数据库文件
 	Load(dbPath string) error
 
-	// 查询IP
+	// Lookup 查询IP
+	// 返回结果有可能为空
 	Lookup(ip string) (*Result, error)
 
-	// 关闭数据库文件
+	// Close 关闭数据库文件
 	Close()
 }
diff --git a/internal/stats/http_request_stat_manager.go b/internal/stats/http_request_stat_manager.go
index c30b61e..2e808f3 100644
--- a/internal/stats/http_request_stat_manager.go
+++ b/internal/stats/http_request_stat_manager.go
@@ -165,7 +165,7 @@ Loop:
 			ip := ipString[atIndex+1:]
 			if iplibrary.SharedLibrary != nil {
 				result, err := iplibrary.SharedLibrary.Lookup(ip)
-				if err == nil {
+				if err == nil && result != nil {
 					this.cityMap[serverId+"@"+result.Country+"@"+result.Province+"@"+result.City]  ++
 
 					if len(result.ISP) > 0 {