Download install Eclipse ADT Plugin:

1) Download the ADT plugin for developing Android apps in eclipse

In enterprise development, many programmers use the Eclipse IDE as the development environment for their applications. In order to make Android app creation, operation and debugging more convenient and fast. The Android development team specifically customized a plugin for the Eclipse IDE: Android Development Tools (ADT)
: Http://dl.google.com/android/ADT-22.3.0.zip
2) Installing the Eclipse plug-in (ADT)
Launch Eclipse, select Help > Install New Software, in the dialog box that appears, click the Add button, enter "ADT" in the Name field of the dialog box, and then click Archive ... to browse and select the ADT plugin zip file that has been downloaded.
Click OK. Return to the Available software view, you will see this plugin, then choose Developer Tools (The following "Android Developer Tools" and "Android Editors"), click Next, and finally restart Eclipse.

Download install Eclipse ADT Plugin: