diff --git a/src/main/java/org/xerial/snappy/SnappyLoader.java b/src/main/java/org/xerial/snappy/SnappyLoader.java
index f802183..bf4c9e8 100755
--- a/src/main/java/org/xerial/snappy/SnappyLoader.java
+++ b/src/main/java/org/xerial/snappy/SnappyLoader.java
@@ -112,7 +112,7 @@ public class SnappyLoader
         return isLoaded;
     }
 
-    static SnappyNativeAPI load() {
+    static synchronized SnappyNativeAPI load() {
 
         if (isInitialized)
             return api;
diff --git a/src/main/resources/org/xerial/snappy/SnappyNativeLoader.bytecode b/src/main/resources/org/xerial/snappy/SnappyNativeLoader.bytecode
index 93bdcce..64c0fe8 100755
Binary files a/src/main/resources/org/xerial/snappy/SnappyNativeLoader.bytecode and b/src/main/resources/org/xerial/snappy/SnappyNativeLoader.bytecode differ
diff --git a/src/main/resources/org/xerial/snappy/SnappyNativeLoader.java b/src/main/resources/org/xerial/snappy/SnappyNativeLoader.java
index 1883166..967912c 100755
--- a/src/main/resources/org/xerial/snappy/SnappyNativeLoader.java
+++ b/src/main/resources/org/xerial/snappy/SnappyNativeLoader.java
@@ -31,7 +31,7 @@ public class SnappyNativeLoader
     private static HashMap<String, Boolean> loadedLibFiles = new HashMap<String, Boolean>();
     private static HashMap<String, Boolean> loadedLib      = new HashMap<String, Boolean>();
 
-    public static void load(String lib) {
+    public static synchronized void load(String lib) {
         if (loadedLibFiles.containsKey(lib) && loadedLibFiles.get(lib) == true)
             return;
 
@@ -44,7 +44,7 @@ public class SnappyNativeLoader
         }
     }
 
-    public static void loadLibrary(String libname) {
+    public static synchronized void loadLibrary(String libname) {
         if (loadedLib.containsKey(libname) && loadedLib.get(libname) == true)
             return;