In this paper, new classes of generalized invex functions called B - (p, r, a)-invex, B - (p, r, a)-quasi invex and B - (p, r, a)-pseudo invex functions are introduced, which are defined by relaxing the definitions of B - (p, r)-invex, B - (p, r)-quasi-invex, B - (p, r)-pseudo-invex functions, then generalized minimax fractional programming involving such functions is reseached, the sufficient conditions for optimality are obtained under weeker convexity.