diff --git a/okhttp-tests/src/test/java/com/squareup/okhttp/MediaTypeTest.java b/okhttp-tests/src/test/java/com/squareup/okhttp/MediaTypeTest.java
index 45dd06a64..25805957a 100644
--- a/okhttp-tests/src/test/java/com/squareup/okhttp/MediaTypeTest.java
+++ b/okhttp-tests/src/test/java/com/squareup/okhttp/MediaTypeTest.java
@@ -107,6 +107,11 @@ public class MediaTypeTest {
     assertEquals("UTF-8", mediaType.charset().name());
   }
 
+  @Test public void testDuplicatedCharsets() {
+    MediaType mediaType = MediaType.parse("text/plain; charset=utf-8; charset=UTF-8");
+    assertEquals("UTF-8", mediaType.charset().name());
+  }
+
   @Test public void testMultipleCharsets() {
     try {
       MediaType.parse("text/plain; charset=utf-8; charset=utf-16");
diff --git a/okhttp/src/main/java/com/squareup/okhttp/MediaType.java b/okhttp/src/main/java/com/squareup/okhttp/MediaType.java
index b0b7f45f5..4d2f1fcf4 100644
--- a/okhttp/src/main/java/com/squareup/okhttp/MediaType.java
+++ b/okhttp/src/main/java/com/squareup/okhttp/MediaType.java
@@ -61,10 +61,13 @@ public final class MediaType {
 
       String name = parameter.group(1);
       if (name == null || !name.equalsIgnoreCase("charset")) continue;
-      if (charset != null) throw new IllegalArgumentException("Multiple charsets: " + string);
-      charset = parameter.group(2) != null
+      String charsetParameter = parameter.group(2) != null
           ? parameter.group(2)  // Value is a token.
           : parameter.group(3); // Value is a quoted string.
+      if (charset != null && !charsetParameter.equalsIgnoreCase(charset)) {
+        throw new IllegalArgumentException("Multiple different charsets: " + string);
+      }
+      charset = charsetParameter;
     }
 
     return new MediaType(string, type, subtype, charset);