Abstract : We prove the Hyers-Ulam stability of a Pexiderized exponential equation of mappings $f, g, h:G\times S\rightarrow\mathbb{C}$, where $G$ is an abelian group and $S$ is a commutative semigroup which is divisible by $2$. As an application we obtain a stability theorem for Pexiderized exponential equation in Schwartz distributions.
