The invention relates to wet-process recovery of tin from anode slime, in particular to a method and a device for recovering metal tin from lead separated slag of copper anode slime. The method comprises the following steps of: according to design requirement, putting lead separated slag roasted sand into a stainless steel kettle designed in the invention, performing water leaching and stirring, adding sodium acetate, and adjusting the pH value by using sodium hydroxide and acetic acid; and starting an anti-corrosion pump to make sodium stannate saturated continuously; and electrolyzing to obtain metal tin. The device mainly comprises a water leaching part, an electrolysis part, a circulation part and a pressure filtration part, and concretely comprises eight key parts, namely the stainless steel kettle, a filter press, a filter, an electrolysis power source, an electrolytic bath, a heating element, the anti-corrosion pump and a thermocouple. After tin electrolysis is stopped, residuecan be pressed by the filter press, and detinned slag and detinned filter liquor. The detinned filter liquor is recycled and used for the next tin electrolysis and recovery procedure. The method and the device have the characteristics of simple and feasible process, common raw materials and equipment, and low cost of the raw materials and equipment.