Type the "egit" in the Install New Software interface of Eclipse,and select the address prompt:
Now ,you found that there are two git,EGit and JGit.After googling them,you may know that the Jgit is the dependence of the Egit,so you have to install the Jgit also.
If you encounter problems whtn you install them at the same time,try to install the Jgit first.
If some items can't be found ,try to ignore them first.
(some problem with Plug-in Import Support)