When you install Gradle plugin in Eclipse, it uses the default C:\Users\Administrator\.gradle as the cache directory.

You may already installed a release of Gradle and build some projects in command line mode with it. And you may set the cache directory in your custom directory.

It's better to use the same cache wherever you use Gradle. For some projects, it takes hours to download all the dependencies, you don't want this.

Select Window -> Preferences and type "Gradle" in filter box.

And set Gradle distribution and Gradle user home like this.

The user home is the same as

 
set GRADLE_USER_HOME=D:\gradle-1.5\.gradle