To obtain a resin composition for powder coating use, free from environmental problem, producible at a low cost, having excellent weather resistance, acid resistance and appearance and useful for automobile parts, or the like, by using a specific vinyl copolymer, a curing catalyst and an ultraviolet absorber, or the like, as essential components at specific ratios.

The objective composition contains (A) 100 pts.wt. of a vinyl copolymer containing a silyl group of the formula (R1 is a 1-10C alkyl, a 6-10C aryl or the like; X is H, a halogen, hydroxy, an alkoxy or the like; (a) is 0-2) as a main crosslinking group and having a glass transition temperature of 40-100°C and a number-average molecular weight of 2,000-20,000, (B) 0.001-10 pts.wt. of a curing catalyst having a melting point of 45°C such as an organotin compound and (C) 0.1-5 pts.wt. of an ultraviolet absorber and/or a light-stabilizer such as hydroxyphenyl benzotriazole compound as essential components. The component A is produced preferably by the copolymerization of a mixture of 3-(meth)acryloxypropyl trimethoxysilane, or the like.