The invention discloses an acid-resisting finishing method for viscose fabric. The method comprises the following steps: a finishing agent is mixed with water to be made into an impregnation liquid, fabric is put into the impregnation liquid for padding, the pick-up rate is 45%-70%, finally, the fabric is washed with water twice or three times, and the viscose fabric can be obtained after water removal and drying. The finishing agent comprises components in parts by weight as follows: 20-50 parts of water, 6-9 parts of sodium polystyrene sulfonate, 5-6 parts of dimethyl terephthalate, 4-7 parts of ethylenediamine tetracetic acid disodium salt, 1-6 parts of acrylamide, 22-25 parts of butyl acetate, 5-8 parts of dimethylcydosiloxane, 3-7 parts of didecyl dimethyl ammonium chloride, 11-16 parts of an isocyanate trimer, 4-8 parts of methyl hydrogen silicone oil, 4-8 parts of o-hydroxybenzoic ester, 4-8 parts of vinyltriethoxysilane and 1-5 parts of fatty alcohol-polyoxyethylene ether. With the adoption of the acid-resisting finishing method, the viscose fabric can be prevented from being wetted and permeated by an acid liquid, can resist corrosion of strong acid and has the advantages of being breathable, comfortable, soft, light, easy to wash and the like.