The invention discloses a water-washable, oil-repellent and water-repellent finishing agent suitable for synthetic fiber fabrics, comprising an auxiliary agent, a penetrant and water, characterized in that: the formula and the proportion of the auxiliary agent in the finishing agent are as follows; the perfluoroalkyl group Acrylate polymer 15 to 20 g/L; carbon polymer 7 to 10 g/L; Nano-scale ultrafine molecular emulsion 7 to 10 g/L. Compared with the conventional process formula, the invention reduces the technical dosage of the auxiliary agent by 10-20g/L, has low cost, and simultaneously reduces the phenomenon of color flowering and material point on the surface of the finished product. The water splashing and oil repellent effect is equivalent to the conventional process. Polar Fleece Glove,Double Layer Glove,Touch Screen Glove Hat & Cap,Scarf & Glove,Buff/ Multifunction Bandana Co., Ltd. , http://www.cnhatcap.com