The present invention provides a resin material and a film made of the resin material, the resin material being able to form a molded body having high transparency, excellent mechanical strength, few foreign matter defects, excellent heat stability, excellent solvent resistance, and extremely good appearance. The resin material contains a thermoplastic resin (A) and a polymer (B) satisfying the following conditions. That is, the polymer (B) is a graft copolymer obtained by multistep polymerization, and at least one step of the multistep polymerization is polymerization of a monomer mixture containing: a (meth)acrylic monomer having a ring structure; and (meth)acrylic acid and/or its salt.