Abstract: The nano photocatalyst in powder form had some problems in the process of catalytic degradation of pollutants, such as easy agglomeration of particles, difficult separation resulted in secondary pollution. A kind of polyurethane-silk fibroin supported BiOBr@CdS (BiOBr@CdS/PU-SF) nanocomposite films were prepared by blending-wet phase transformation in situ synthesis method. The XRD, FTIR, SEM, XPS, UV-Vis diffuse reflectance spectra (UV-Vis DRS) and photoluminescence spectra (PL) were used to characterize the crystal structure, micromorphology, surface element valence and optical properties. The results show that the semiconductor nanocompo-sites are formed between BiOBr and CdS in the BiOBr@CdS/PU-SF composite film, which not only improve the visible light absorption capacity of a single semiconductor, but also effectively inhibit the recombination of photogenerated carriers. The photocatalytic activity was evaluated by degradation of antibiotic wastewater (Tetracycline hydrochloride (TC) as model pollutant) under visible light irradiation. Among them, a 1:1 molar ratio of Bi and Cd for (1:1)BiOBr@CdS/PU-SF composite film shows the highest removal rate of TC (70.3%), which is the 1.33 times and 2.45 times of BiOBr/PU-SF and CdS/PU-SF composite films, respectively. The pseudo-first-order kinetic constants of TC degradation are 1.63 and 3.58 times of BiOBr/PU-SF and CdS/PU-SF composite films, respectively. Moreover, the composite film can be separated and recovered without centrifugation and filtration, and it can still maintain more than 80% of the original degradation rate after recycling for five times.