The invention relates to a two-package curing type polyurethane paint and preparation thereof. The raw material system of the paint comprises a polyether polyol, a isocyanate, a small molecular chain expander and a solvent, wherein polydihydrofuran ether glycol with molecular weight between 700 to 1500 is used as the plyether polyol; methyl diphenylene diisocyanate is used as the isocyanate, 1,4-butanediol is used as the small molecular chain expander, dimethylformamide is used as the solvent. Weight proportion between the plyether polyol, the small molecular chain expander and the solvent is 1:0.7 - 0.85:8 - 15. Colloidal viscosity of the polyether polyol at 25 DEG C. is between 3000 and 2000cps. The paint is obtained by primarily charging DMF as the solvent, the polyether polyol and the chain expander into the reaction container simultaneously at one time, and then gradually charging the isocyanate for the reaction. By using MDI to substitute TDI for preparation of the polyurethane paint preparation, the invention is low in viscosity, great in levelability, easy for hardness adjustment, low in cost, safe and environment friendly in use.