Well, do you mean the manga or the anime?
For the anime it's just "Ghost in the Shell".
For the manga it's "Koukaku Kidoutai-The Ghost
in the Shell".The kanji used for "Koukaku 
Kidoutai" are really difficult to read(even for
japanese).After my japanese isn't very good
I've asked around for translation; it goes in the
direction of "Mobile Armoured Tactical Group".
(Please anyone correct me if I'm wrong.)