The invention discloses a method for comprehensively recycling vanadium, gallium, aluminum and silicon in coal gangue. The method comprises the steps that firstly, the coal gangue is subjected to crushing and grinding pretreatment, then the treated coal gangue is uniformly mixed with sodium-potassium mixed salt, then the mixed sample is placed in a roasting furnace to be roasted, then the roastedsample is subjected to stirring water leaching, a next batch of roasted samples are circularly leached for 5-11 times after the water leaching solution is collected, vanadium-enriched liquid is obtained after cyclic leaching is finished, and V2O5 with the purity larger than 99.5% is obtained after vanadium precipitation and calcination of the vanadium-enriched liquid; water leaching residue and mixed acid are uniformly mixed for stirring and acid leaching, and the acid leaching residue is washed with water to obtain kaolin with whiteness larger than 95; and a pickling solution and a mixed medicament of N964, Cyanex 257, TBP and sulfonated kerosene are subjected to vibration extraction to obtain a saturated organic phase, back extraction is carried out on the saturated organic phase and a mixed solution of hydrofluoric acid and hydrochloric acid to obtain gallium-rich liquid, and precipitation and calcination are carried out on the gallium-rich liquid to obtain gallium trioxide with thepurity larger than 99.8%. The method has the advantages that treatment operation is easy, various objects are recycled, and the comprehensive recovery rate of vanadium, gallium, aluminum and siliconis high.