To provide a transparent resin molded body provided with an excellent reflow heat-resistance and optical characteristic, and to further provide an optical lens and an optical film comprising the transparent resin molded body and excellent in heat-resistance and optical characteristic.

The resin molded body is obtained by molding a molding material containing a thermoplastic resin and crosslinking the thermoplastic resin. The thermoplastic resin is selected from a resin in which average transmittance in a range of 600-1,000 nm in a molded body having a thickness of 2 mm becomes 60% or higher. The resin molded body is characterized in that average transmittance in a range of 600-1,000 nm when it is heated at 200C for 10 minutes and the thickness is made to 2 mm is 60% or higher. The optical lens and the optical film are formed by the transparent resin molded body.