John,

Im putting up drywall in my basement. Two of my walls are exterior
walls and my studs are about 6 inches from the wall. Should I put up
plastic as a moisture barrier before putting up the drywall. Im not
installing any type of insulation.

If you are going to install a plastic moisture barrier, you would want it
against the concrete wall, not behind the drywall. The idea is to keep
moisture out of the wall, not trap moisture in the wall.

I'm assuming, of course, your basement walls do not leak any. If that's the
case, you'll probably need some kind of perimeter drain and a sump pump.

As another poster mentioned, a paintable membrane like Drylok might be a
better option for a foundation wall than the plastic sheet.

Anthony