The tannic acid (TA)-polyvinylidene fluoride (PVDF) nanofiltration membrane is prepared by simply coating tannic acid and polydopamine. The chemical elements and morphology of the nanofiltration membrane surface are characterized by infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Meanwhile, the hydrophilicity and underwater anti-oil-adhesion performance of the modified membrane are also evaluated. Besides, the separation performance for dyes such as Direct red, Evans blue, Congo red, Reactive yellow, and Brilliant blue is explored. The result shows that the surface roughness of the obtained membrane increases slightly after modification. With the increase of TA concentration, the hydrophilicity of the membrane surface is significantly enhanced. When the TA concentration reaches 2wt%, the surface hydrophilicity of the prepared TA-PVDF nanofiltration membrane is almost stable, and the water contact angle of the modified membrane is 44.6°. Additionally, the obtained membrane with the underwater oil contact angle of 157.2° is characterized as a superoleophobic one. There is a strong interaction between the modified membrane and water molecules. On account of the hydration layer formed on the membrane surface, the obtained membrane can completely resist the contamination of oil under the water. The rejection rate of 2wt% TA-PVDF nanofiltration membrane is more than 96.5% for several dyes, and its permeating fluxes of Direct red, Evans blue, Congo red, Reactive yellow, and Brilliant blue all exceed 65.7 L/(m2?h?bar). In addition, the modified membrane keeps the permeance nearly unchanged during the dyes' separation process, exhibiting strong stability for dyes separation. Compared to the works published recently, the prepared nanofiltration membrane with 97% rejection rate for Congo red has a higher permeating flux. The obtained membrane shows a superior separation capacity and efficiency for the dyes, demonstrating a good application prospect in industrial dye wastewater separation.