Abstract: In recent years, the problem of environmental pollution have become more and more serious. Photocatalytic technology plays an important role in treating sewage and purifying air. In this paper, the effect of different nano-TiO2 dosage on the thermal properties, mechanical properties, photocatalytic properties of PA6/TiO2-GO composite were studied by the differential scanning calorimeter, electronic universal tensile testing machine, visible spectrophotometer and other instruments. The results of the study show that: with the increase of nano-TiO2 content, the melting point of PA6/TiO2-GO composites gradually decreases, the crystallinity increases first and then decreases (the crystallinity of composites is greater than that of pure PA6). The breaking strength gradually decreases. The elongation at break gradually increases. The ability of nano-TiO2 to photocatalytic degradation of methylene blue solution becomes stronger and stronger. At the same TiO2 content, adding GO can effectively improve the photocatalytic degradation of TiO2, and the photocatalytic degradation capability can be improved by about 10%.