PURPOSE: A methacryl resin having a specified composition and being excellent in flow, heat resistance, moldability and mechanical strength, prepared by polymerizing methyl methacrylate with an acrylate ester and/or other methacrylate esters.

CONSTITUTION: A methacryl resin which is a copolymer prepared by copolymerizing a monomer mixture consisting of (A) 96W99% methyl methacrylate, (B) 4W1% acrylate ester and/or methacrylate ester other than methyl methacrylate and which has a weight-average MW of 8W15×104, a MW distribution index (number-average MW/weight-average MW) of 2.3W3.0, a low-MN portion (≤1.0×104) content ≤10.0%, a super-MW portion (≥1.0×106) content ≤1.0%, a syndiotactic polymer content of 70W85% and a thermal decomposition index ≤5.