A novel flexible graphitic carbon nitride loaded SiO2 (g-C3N4/SiO2) nanofibrous membrane was fabricated for photocatalytic degradation of dyes. The g-C3N4 nanosheets were directly grown on the electrospun SiO2 nanofiber surface by thermal condensation of urea precursor. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy detections confirmed the successful preparation of the g-C3N4 nanosheets. The g-C3N4 nanosheets with a few layers in thickness were tightly attached on the SiO2 nanofiber surface. The obtained g-C3N4/SiO2 catalysts exhibited high catalytic performance towards decomposition of Rhodamine B under visible light irradiation. The photocatalytic activity remained above 90% within 80 min illumination even after five cycles. Due to the easy preparation and high photocatalytic performance, as well as convenient collection for reuse, the obtained g-C3N4/SiO2 hybrid membranes are promising catalysts for practical application.