diff --git a/src/main/java/org/ttzero/excel/entity/I18N.java b/src/main/java/org/ttzero/excel/entity/I18N.java
index e4c8ebd6..e6e70eaa 100644
--- a/src/main/java/org/ttzero/excel/entity/I18N.java
+++ b/src/main/java/org/ttzero/excel/entity/I18N.java
@@ -22,19 +22,29 @@
 import java.io.Reader;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
+import java.util.HashMap;
 import java.util.Locale;
+import java.util.Map;
 import java.util.Properties;
 
 /**
  * @author guanquan.wang on 2018-10-13
  */
 public class I18N {
-    private final Properties pro;
+    /**
+     * Here converted to HashMap is to improve performance,
+     * Properties extends to Hashtable All methods are synchronous methods,
+     * I18N only needs to read without writing, so converting to HashMap can greatly improve performance
+     */
+    private Map<String, String> pro;
 
     public I18N() {
+        init();
+    }
+
+    void init() {
         Locale locale = Locale.getDefault();
         String fn = "message._.properties";
-        pro = new Properties();
         try {
             InputStream is = I18N.class.getClassLoader().getResourceAsStream("I18N/" + fn.replace("_", locale.toLanguageTag()));
             if (is == null) {
@@ -42,12 +52,21 @@ public I18N() {
             }
             if (is != null) {
                 try (Reader reader = new InputStreamReader(is, StandardCharsets.UTF_8)) {
+                    Properties pro = new Properties();
                     pro.load(reader);
+                    Map<String, String> map = new HashMap<>(pro.size());
+                    for (Map.Entry<Object, Object> entry : pro.entrySet()) {
+                        map.put(entry.getKey().toString(), entry.getValue().toString());
+                    }
+                    this.pro = map;
                 }
             }
+            // FIXME classpath
         } catch (IOException e) {
             // nothing...
         }
+
+        if (pro == null) pro = new HashMap<>();
     }
 
     /**
@@ -57,7 +76,7 @@ public I18N() {
      * @return I18N string
      */
     public String get(String code) {
-        return pro.getProperty(code, code);
+        return pro.getOrDefault(code, code);
     }
 
     /**
@@ -68,7 +87,7 @@ public String get(String code) {
      * @return I18N string
      */
     public String getOrElse(String code, String other) {
-        return pro.getProperty(code, other);
+        return pro.getOrDefault(code, other);
     }
 
     /**
@@ -79,7 +98,7 @@ public String getOrElse(String code, String other) {
      * @return I18N string
      */
     public String get(String code, String... args) {
-        String msg = pro.getProperty(code, code);
+        String msg = pro.getOrDefault(code, code);
         char[] oldValue = msg.toCharArray();
         int[] indexs = search(oldValue);
         int len = Math.min(indexs.length, args.length), size = 0;