nikon 50mm f1.8 lens for nikon D70
50mm 1.8f G is good ,but I want to know if AF will auto focus with the D70 or do I need AFS
You don't need AF-S. The D70 has an in-camera motor.
You don't need to have AFS but I would still get the newer one as it is a better lens and not expensive. That said I personally would not necessarily want a 50mm lens on DX and would get the 35mm f1.8 in preference.
My 1992 50 F1.8 AF worked just fine on my D70s. It will autofocus without a problem.
However, I never liked the field of view of that lens on DX. I was a lot happier with the 35F2. I always thought the main reason people got the 50 f1.8 for DX cameras was the incredibly cheap price. The next cheapest F1.8 / F2.0 lens was triple the price.
Now, comparing 35F1.8 dx and 50F1.8 g at the same price, I'd get the 35 for DX and the 50 for FX.
You haven't stated how you intend to use this lens on a D70.
As others have mentioned, any Nikkor 50mm with autofocus will work well with the D70 (ie D or AF-S versions).
50mm works out to an effective focal length of 75mm (in FX or 35mm film parlance). This focal length is a bit long for general purpose shooting. However, it is very good for portraits and also works well for multi-shot panoramas that are stitched together in computer.