diff --git a/android-jdk6-redkale/src/org/redkale/convert/Factory.java b/android-jdk6-redkale/src/org/redkale/convert/Factory.java
index cb00f6e25..b03e975d0 100644
--- a/android-jdk6-redkale/src/org/redkale/convert/Factory.java
+++ b/android-jdk6-redkale/src/org/redkale/convert/Factory.java
@@ -84,7 +84,6 @@ public abstract class Factory<R extends Reader, W extends Writer> {
             this.register(Number.class, NumberSimpledCoder.instance);
             this.register(String.class, StringSimpledCoder.instance);
             this.register(CharSequence.class, CharSequenceSimpledCoder.instance);
-            this.register(StringBuilder.class, CharSequenceSimpledCoder.instance);
             this.register(java.util.Date.class, DateSimpledCoder.instance);
             this.register(BigInteger.class, BigIntegerSimpledCoder.instance);
             this.register(InetAddress.class, InetAddressSimpledCoder.instance);