In this paper we prove the superstability of a generalized exponential functional equation $f(x+y)=a^{2xy-1}g(x)f(y)$. It is a generalization of the superstability theorem for the exponential functional equation proved by Baker. Also we investigate the stability of this functional equation in the following form : ${frac{1}{1+{delta}}}{leq}{frac{f(x+y)}{a^{2xy-1}g(x)f(y)}}{leq}1+{delta}$.