The invention relates to a method for leaching and recovering molybdenum from ammonia leaching residue, which is characterized by comprising the steps: (1) dehydrating and drying the ammonia leaching residue; (2) sieving the dried ammonia leaching residue, and dividing into screen overflow and screen underflow; (3) adding sodium carbonate and water into the screen overflow for stirring and slurrying; (4) heating liquid slurry to 95-100 DEG C, dripping sodium hypochlorite solution into the liquid slurry, and stirring at the constant temperature; and after dripping sodium hypochlorite solution,filtering and obtaining primary alkali leaching solution of the molybdenum; (5) adding the sodium carbonate and the water into the screen underflow for stirring and slurrying; (6) dripping the primary alkali leaching solution of the molybdenum obtained in the step (4) in the liquid slurry obtained in the step (5), and obtaining the alkali leaching solution of the molybdenum; and (7) recovering the molybdenum in the alkali leaching solution of the molybdenum. The method has simple and easy technique, reaction carried out at the normal pressure and easily controlled leaching process, and is simple and convenient in operation, safe and reliable, stable in technique, low in production cost and high in leaching rate.