Surface protective film

The invention provides a surface protective film having a laminated structure including an adhesive layer, a back layer, and a middle layer, that does not cause an increase in adhesion strength to optical films, such as polarizers and retardation films, which must achieve a high standard of quality so that adherends will suffer from no dents or no deformation caused particularly by minute fisheye defects and roll-up creases. Furthermore, the surface protective film does not contaminate adherends, nor cause any defects such as dents and deformations in adherends. To solve the abovementioned problem, the present invention employs the following means. Specifically, the surface protective film of the present invention comprises a three-layer laminated structure including an adhesive layer, a middle layer and a back layer, wherein the adhesive layer is formed from an ethylene-±-olefin copolymer, an ethylene-methyl methacrylate copolymer, or a mixture thereof, the middle layer is formed primarily from a polyethylen