: Industrial wastewater treatment is very important because of the large amount of water pollutants and the growing need for safe water. Dyes are one of the most important sources of water pollution which are released into the soil and aquatic ecosystems, forming carcinogenic compounds due to anaerobic degradation. Therefore, it is necessary to purify the wastewater before its entrance into the environment. Through the advanced oxidation process, photocatalysts are able to oxidize organic pollutants to harmless products and protect the environment. In this project, ZnO nanofibers were doped with silver (Ag) and graphene-oxide (GO), preventing the electron-hole recombination process and accelerating the photocatalyst reactions under visible light. Ag-ZnO/rGO nanofibers were synthesized by the calcination of electrospun nanofibers from a PVA solution containing appropriate zinc acetate, silver nitrate and graphene oxide. Calcination was done at 600 ?C and the temperature rate of 3?C/min for 5hr. Nanofibers were characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), photoluminescence (PL), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The FTIR, XRD and EDS results confirmed the formation of wurtzite ZnO crystals, cubic Ag crystals, and rGO after the calcination treatment. Also, FESEM images revealed the formation of uniform and bead free nanofibers before and after calcination. Further, the results of methylene blue photocatalytic decolorization using ZnO nanofibers containing 1, 2, 3, 4 and 5 %wt GO with and without 8%wt of Ag showed that hybrid ZnO nanofibers containing 8 %wt of Ag/1 % rGO , and 3%wt rGO (without Ag) had the best photocatalytic activity. Then RB13 photocatalytic degradation was investigated using ZnO, ZnO/3%rGO and Ag-ZnO/1%rGO nanofibers. The results showed that the photocatalytic activity was enhanced with the increase in pH and the maximum efficiency was attained at the pH of 13. Also, increasing the amount of Ag-ZnO/rGO nanofibers enhanced the RB13 photocatalytic degradation. Reduction of the photocatalytic activity was observed with increasing the dye concentration. No significant change in the photocatalytic performance of the nanofibres after three cycles of use indicated a very good recovery, as well as the economical and environmentally friendly Ag-ZnO/1%rGO nanofibers. The photocatalytic efficiency of the 10 ppm RB13 solution while using 0.01 g of ZnO, ZnO/3%rGO and Ag-ZnO/1%rGO nanofibers at the pH of 13, after 135 min, under visible light was about 58% and 91% and 98%, respectively. Reduction in the COD of the treated RB13 solutions also revealed the enhancement of the wastewater quality due to the decomposition of organic contaminants during the photocatalytic reaction, as well as the color removal. The results also showed that the best models fitting the kinetic data of ZnO, ZnO/3%rGO and Ag-ZnO/1%rGO nanofibers were pseudo-first-order.