Clothing functionalization is a research hotspot in the field of modern clothing, and the design and development of functional textiles are one of the important links. Strong UV light will cause skin sunburn and even canceration, especially the special population such as patients with albinism need ultraviolet protection. It is of great practical significance to develop UV resistant functional textiles. Graphene oxide has been widely used because of its excellent properties. It can be used in the development of conductive, antibacterial, UV resistant and other functional textile clothing. In this paper, graphene oxide is attached to cotton fabric fibers by adsorption and deposition methods, and the environmentally friendly reducing agent L-ascorbic acid is used to reduce it to obtain reduced graphene oxide UV-resistant cotton fabrics with different reduction degrees. The reduction degree of the reduced graphene oxide cotton fabric was characterized by reflectance curve, Raman spectrum and XPS. The results show that the reflectance of the reduced graphene oxide cotton fabric decreases with the increase of the reductant concentration after the reduction of graphene oxide on the surface of cotton fabric; the intensity of D and G peaks in the Raman spectrum changes obviously, the ID/IG value increases gradually with the increase of the reductant, and the reduction degree increases; the XPS spectrum shows that the carbon and oxygen content of the reduced graphene oxide cotton fabric increases before and after the reduction, the content of carbon increased, the content of oxygen decreased, and the ratio of carbon to oxygen increased from 2.26 to 2.90, indicating that the content of oxygen-containing functional groups decreased. Finally, the UV resistance of the reduced graphene oxide cotton fabric with different reduction degree was tested. When the concentration of L-ascorbic acid reducing agent was 7 and 10 mg·mL-1, the UPF value of the reduced graphene oxide cotton fabric was between 100～120, and the UV transmittance was below 2%, which was significantly improved compared with the blank cotton fabric. The reduced graphene oxide cotton fabric studied in this paper can be used in the design and development of cotton textiles and clothing to meet the demand of clothing anti UV function, and it has great market potential and application prospect.