The invention discloses a process for removing impurities in zinc ash. According to the process, the by-product zinc ash in industrial production is taken as the raw material, an impurity removing additive composed of stearic acid and cerotic acid is added, high-temperature roasting is performed, and by controlling the process conditions including the roasting temperature, the rotating speed of aroasting furnace, the roasting time and the like, a zinc ash end-product with the zinc element content above 73.5% and the chlorine element content being zero is finally obtained.