In this paper some conditions for a skew group ring or a crossed product to have finite weak global dimension are given.Using these results we obtain some necessary conditions and some sufficient conditions for a skew group ring or a crossed product to be a Dubrovin valuation ring.IfR*Gis a skew group ring, where the coefficient ringRis a commutative ring andGis a finite group, then we prove that the conditions we obtained become necessary and sufficient conditions.In particular, ifRis a commutative valuation ring, thenR*Gis a Dubrovin valuation ring if and only ifGT=<1>,whereGTis the inertial group ofR.