My wife us citezen , am indian(ex resident) and my son is claiming my wife as dependent, can he or other person claim me as a dependent in 1040? I do file my tax return in usa with small income I am receiving.

No, because you are NOT a U.S. citizen or green card holder and you are NOT physically loacted in the U.S.

Your wife CAN be claimed because she is a U.S. citizen and the parent of a U.S. resident, even if she is located in India.

I am green card holder but out from us for 90 days. So what that leads to?

If you are a green card holder, then you are considered to be a resident of the U.S.

In tha case, provided your son has provided more than HALF of your total support, he can claim you as a dependent/