The present invention relates to spinning method of polymer and its composite material, and aims at simplifying spinning process and raising the titer and continuity of spun fiber. The spinning method includes the following steps: mixing polymer with diluting and dispersing solvent to form mixed liquid; provides a kind of liquid with polar molecule and insoluble to the mixed liquid; adding the mixed liquid into the liquid to form film on the surface of the liquid; and providing one upwards drawing device with tip to contact the film and upwards drawing the device to draw fiber from the mixed liquid.