The invention discloses a three-way catalytic converter with a cleaning mechanism. The three-way catalytic converter comprises a catalytic converter housing, wherein the catalytic converter housing is a cylinder with two ends closed, and is internally and fixedly provided with a catalyst; an air outlet is formed in the bottom surface of the catalytic converter housing; an air inlet pipe is arranged in the top surface of the catalytic converter housing, and is communicated with a three-way valve; the rest two ends of the three-way valve are communicated with an exhaust pipe and a ventilating pipe of an automobile respectively; the ventilating pipe is communicated with an outlet of an air pump; the outlet of the air pump is communicated with an air guide pipe; the air guide pipe is communicated to a cleaning agent bottle; the cleaning agent bottle contains a cleaning agent; a liquid outlet pipe is inserted into the cleaning agent bottle; one end of the liquid outlet pipe is arranged below the liquid level of the cleaning agent; the other end of the liquid outlet pipe is communicated with a spray nozzle; and the spray nozzle is fixed to the inner wall of the top surface of the catalytic converter housing. The three-way catalytic converter with the cleaning mechanism can realize the effect of being cleaned automatically without being dismounted from the automobile.