A plastic film comprising a multi-layer structure obtained by co-casting film formation or sequential-casting film formation of two or more layers of polyarylate having a glass transition temperature of 250° C. or higher and having a chemical structure represented by the following formula: wherein X represents a linking group having a naphthalene or biphenyl structure and A is represented by the following formula: wherein R1 and R2 represent an alkyl group or aryl group, j and k are an integer of from 0 to 4.