The invention discloses a surface modification method for a polytetrafluoroethylene product. The method comprises the following steps of: coating polyethylene glycol on the surface of the polytetrafluoroethylene product, and then performing surface modification on the polytetrafluoroethylene product coated with the polyethylene glycol by adopting a plasma treatment method. Compared with the prior art, the polyethylene glycol element is introduced on the surface of the polytetrafluoroethylene product so as to effectively improve the surface activity of the polytetrafluoroethylene product, reduce the contact angle, improve the surface energy, remarkably improve the wetting property and the adhesion property of the polytetrafluoroethylene product and keep the polytetrafluoroethylene product for long time; and in addition, the method has little influence on the chemical property of the polytetrafluoroethylene product, has the advantages of convenient for operation, simple process, high processing speed, good treatment effect, low cost, energy conservation and emission reduction, is not easy to cause environmental pollution, and is more suitable for industrialized production.