The invention provides a method for recovering gallium from gallium nitride-containing wastes. The method comprises the following steps: 1, crushing the gallium nitride-containing wastes; 2, washing gallium nitride-containing waste powder obtained in step 1, drying, adding the dried powder to concentrated sulfuric acid, heating, and filtering to obtain a filter residue A; 3, adding water to the filter residue A, boiling for dissolving, and filtering to obtain a filtrate B and a filter residue B; 4, adding the filter residue B to aqua regia, reacting while stirring, and filtering to obtain a filter residue C and a filtrate C; 5, washing the filter residue C, drying, adding the dried filter residue C to a KOH-glycol solution, carrying out a stirring or ultrasonic vibration reaction, and filtering to obtain a gallium-containing filtrate; 6, extracting the gallium-containing filtrate by Kelex-100, and separating to obtain a gallium-containing organic phase; 7, washing the gallium-containing organic phase with an HCl solution, and back-extracting through using HCl to obtain a gallium-containing aqueous solution; and 8, carrying out vortex selective electro-deposition of gallium. The method can effectively solve the treatment problem of various gallium nitride-containing wastes, changes wastes into valuables, and effectively recovers metallic gallium in order to obtain large economic benefits.