In this paper, we discuss in detail the behaviour of ideals of a P(r,m) γ-seminear-ring. We have shown that in a P(1, 2)(P(2,1)) γ - seminear-ring, every left ideal (right ideal) of R is also an ideal. We also obtain the notions of prime ideal, completely prime ideal and primary ideal coincide in a P(r, m) γ - seminear-ring which admits mate functions.