The invention discloses a protection method of local scouring of a pier, and belongs to the technical field of bridge reinforcing. The protection method comprises the following steps of 1, determininga reinforcing area of a to-be-reinforced pier; 2, determining the reinforcing depth H of the to-be-reinforced pier; 3, conducting grouting reinforcement. By means of the protection method of local scouring of the pier, the reinforcing effect of local scouring of the pier is good, the durability is high after reinforcement, the maintenance cost in the later period is low, and it can be achieved that reinforcement is not need anymore once reinforcement is conducted.