A resin material which has improved weathering (light) stability while retaining excellent properties inherent in a polyacetal resin, such as appearance and rigidity. The branched polyacetal resin composition comprises 100 parts by weight of (A) a branched polyacetal copolymer having oxymethylene groups as the main repeating units and branched units represented by general formula (I), 0.01 to 5 parts by weight of (B) a weathering (light) stabilizer, and 0.01 to 5 parts by weight of (C) a hindered amine substance. (In the formula, m and n each is an integer of 0 to 5, provided that m+n is 1 to 5; and R represents a monovalent organic group having a molecular weight of 40 to 1,000.)