Abstract. Let (Ω, F, {F t }, P ) be a complete probability space with filtration {F t }, (X , H, µ) an abstract Wiener space of M-type 2, and {B t : t ≥ 0} an X -valued Brownian motion such that the distribution of the random function t −1/2 B t : Ω → X is µ for any t > 0. We consider the strong solutions to a set-valued stochastic differential equation with a set-valued drift and a single valued diffusion driven by dB t . Under some suitable conditions, the existence and uniqueness of strong solutions are obtained.