The invention discloses a thrombus removing device capable of preventing damage on an inner wall of a blood vessel. The thrombus removing device of the invention comprises an outer support sleeving device and an internal removing device; the outer support sleeving device comprises a metal sleeve and an outer sleeving tube; an infrared detection device is arranged on an end surface of the metal sleeve which faces a cutting device; the internal cleaning device comprises a first thrombus channel, a second thrombus channel and the cutting device; the cutting device comprises blade support strips, blades, a pin roll, an air cylinder, a rubber sleeve and projected strips; an internal removing device of the thrombus removing device supports one side of the inner wall of the blood vessel with the thrombus through the outer support sleeving device before working to prevent the inner wall of the blood vessel from being scratched during a removing process; a motor drives the second thrombus channel to rotate and the blade support stripes expand through the air cylinder; and infrared detection device on the outer support sleeving device can detect an opening position of the blades. The thrombus removing device capable of preventing damage on inner wall of blood vessel can provide convenience to medical staff to control the blades not to go beyond a scratching-proof fillet and guarantees that the inner wall of the blood vessel is not damaged while the vessel is unblocked.