Abstract. We present in this paper sufficient conditions for the topological triviality of families of germs of functions defined on an analytic variety V . The main result is an infinitesimal criterion based on a convenient weighted inequality, similar to that introduced by T. Fukui and L. Paunescu in [8]. When V is a weighted homogeneous variety, we obtain as a corollary, the topological triviality of deformations by terms of non negative weights of a weighted homogeneous germ consistent with V . Application of the results to deformations of Newton non-degenerate germs with respect to a given variety is also given. §1. Introduction Let V, 0 be the germ of an analytic subvariety of k n , k = R, or C and let R V (respectively C 0 -R V ) be the group of germs of diffeomorphisms (respectively homeomorphisms) preserving V, 0, acting on germs h 0 : k n , 0 → k, 0. The aim of this paper is to study topologically trivial deformations of R Vfinitely determined germs h 0 . The main result is Theorem 3.4 in which we introduce a sufficient condition for the C 0 -R V -triviality of families of map germs h : k n × k, 0 → k, 0, h(x, 0) = h 0 (x), based on a convenient weighted inequality, similar to that introduced by T. Fukui and L. Paunescu in [8]. A non weighted version of this result first appeared in [13]. There, the sufficient condition for topological triviality is formulated in terms of the integral closure of the tangent space to the R V -orbit of h t .As an application of the results, when V is a weighted homogeneous analytic variety, we prove that any deformation by non negative weights of an R V -finitely determined weighted homogeneous germ (consistent with V ) is topologically trivial. This result was previously proved by J. Damon