Let E be an infinite-dimensional locally convex space, let { n } be a weakly convergent sequence of probability measures on E, and let {E n } be a sequence of Dirichlet forms on E such that E n is defined on L 2 ( n ). General sufficient conditions for Mosco convergence of the gradient Dirichlet forms are obtained. Applications to Gibbs states on a lattice and to the Gaussian case are given. Weak convergence of the associated processes is discussed.