In this paper we study to solve the o f additive (β1,β2)-f unctional inequality with n−variables and their Hyers-Ulam stability. First are investigated in complex Banach spaces with a fixed point method and last are investigated in complex Banach spaces with a direct method. I will show that the solutions of the additive (β1,β2)-f unctional inequality are additive mapping. Then Hyers−Ulam stability o f these equation are given and proven. T hese are the main results o f this paper .