The invention discloses a sealing structure for a car air conditioner. The sealing structure is characterized in that a mounting hole is formed in the mounting position of a shell, and U-shaped mounting grooves are formed in the periphery of the mounting hole; and a throttle shaft is inserted into the mounting hole, and U-shaped mounting strips are arranged on the periphery of the throttle shaft to adapt to the U-shaped mounting grooves of the sealing structure. Through the structure, during mounting, the positioning effect is achieved, the air leakage and squealing phenomena are avoided, theperpendicularity of throttle shaft hole grooves is better guaranteed, the concentricity of two holes corresponding to the throttle shaft is ensured, and thus throttle rotation is better facilitated; and the effective contact area is increased, the risk of breaking of the end of the throttle shaft in the resistance movement process is reduced, and the strength of the position corresponding to the shell is effectively improve.