diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
index 786119b49f8..50961ef266d 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/DefaultCodegen.java
@@ -1122,12 +1122,18 @@ public class DefaultCodegen {
     }
 
     /**
-     * Output the proper model name (capitalized)
+     * Output the proper model name (capitalized).
+     * In case the name belongs to the TypeSystem it won't be renamed.
      *
      * @param name the name of the model
      * @return capitalized model name
      */
     public String toModelName(final String name) {
+        // Don't do any kind of renaming to language specific types
+        if(typeMapping.values().contains(name)) {
+            return name;
+        }
+
         return initialCaps(modelNamePrefix + name + modelNameSuffix);
     }
 
diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java
index c245125f80a..e1bc4f3a0d8 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/AbstractJavaCodegen.java
@@ -343,6 +343,11 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
 
     @Override
     public String toModelName(final String name) {
+        // Don't do any kind of sanitizing to Java types (e.g. BigDecimal)
+        if(typeMapping.values().contains(name)) {
+            return name;
+        }
+
         final String sanitizedName = sanitizeName(modelNamePrefix + name + modelNameSuffix);
 
         // camelize the model name