Manufacturing method of optical film, optical film, polarizing plate, and liquid crystal display device suppressing non-uniform display in the display device due to environment change using a resin originated from plants

The issue of the invention provides a manufacturing method of wide optical film, optical film, polarizing plate, and liquid crystal display device having small retardation value in an in-plane direction and a thickness direction, and suppressing the non-uniform display in the display device due to environment change using a resin originated from plants. The solution is that the manufacturing method of optical film, optical film, polarizing plate, and liquid crystal display device according to the invention characters comprising steps of forming a long film from a coating containing a cellulose ester resin having a total degree of acetyl group substitution of 2.30 to 2.60 and a sugar ester having a furanose structure or a pyranose structure, and a step of stretching the long film, wherein the retardation value Ro is 0 to 10nm, and Rt is -10 to 10nm. The step of stretching the long film, according to the sequence, comprises steps of a first step obtaining a first stretched film, and a second step obtaining a se