A methacrylic resin composition in which a star block copolymer (B) in the form of particles is dispersed in a matrix (A) composed of a methacrylic resin comprising not less than 50% by mass of a methyl methacrylate unit. The methacrylic resin composition is obtained by bulk-polymerizing or solution-polymerizing 100 parts by mass of a monomer mixture (A′) containing 50 to 100% by mass of methyl methacrylate and 0 to 50% by mass of other vinyl monomer copolymerizable with the methyl methacrylate, in the presence of 1 to 80 parts by mass of the star block copolymer (B) comprising a polymer block (a) composed of a (meth)acrylic acid alkyl ester unit and a polymer block (b) composed of a conjugated diene compound unit, until the polymerization conversion of the monomer reaches 70% by mass or more.