The invention discloses a method for recovering gallium from fly ash. The method comprises the following steps: a dissolving step: adding fly ash into hydrochloric acid, mixing and filtering to obtain a gallium-containing solution; a separation step: carrying out ion adsorption on the gallium-containing solution through CL-TBP levextrel resin to obtain adsorption levextrel resin; eluting the adsorption levextrel resin to obtain eluate; an electrolysis step: electrolyzing the eluate to obtain gallium. In the method disclosed by the invention, gallium element in the fly ash can be converted into Ga<3+> by utilizing hydrochloric acid; the gallium-containing solution passes through the CL-TBP levextrel resin to selectively adsorb Ga<3+> in the gallium-containing solution into the CL-TBP levextrel resin; after the adsorption levextrel resin is eluted, the eluate with high concentration of gallium is obtained; the eluate is electrolyzed to obtain gallium with higher purity. The method only comprises the steps of dissolving, adsorbing, eluting and electrolyzing the fly ash, so that the method is easy in technological operation, and lower in recovery cost.