The invention provides a rapid-annealing method for growing large-size sapphire single-crystal with the SAPMAC method. The SAPMAC method is adopted for growing sapphire single-crystal; after growing is finished, the vacuum degree of a crystal growing furnace is kept; electric power source is not cut off; heating power is lowered according to certain temperature reduction procedure until heating power is zero; and then inert gases are led in for rapid cooling. The invention has the beneficial effects that: 1. crystal dislocation density can be lowered, the lattice vacancy of crystal with big diameter and high expansion factor can be lowered, defect concentration such as distortion of lattice, dislocation and the like can be eliminated, crystal cleavage is avoided, and crystal quality and utilization factor can be improved; 2. in-situ annealing of crystal can be realized, crystal growing cycle can be shortened under the precondition of ensuring crystal quality; and 3. production cost canbe lowered.