The invention discloses a water cooling and air cooling combined radiator with a distance sensing function. The water cooling and air cooling combined radiator with the distance sensing function comprises a frame; a fixed bracket is arranged on each of the left side and the right side of the frame; mounting holes are formed in each fixed bracket; a water inlet is formed in the upper part of the left side of the frame; a water outlet is formed in the lower part of the left side of the frame; a radiating core body is arranged in the centre of the frame, and comprises a plurality of radiating pipes which are arranged in parallel; fins are uniformly distributed on the outer sides of the radiating pipes; the cross sections of the inner parts of the radiating pipes are arranged to be circular; a radiating fan is fixedly mounted on one fixed bracket and covers the uper side of the radiating core body; the radiating fan comprises a machine body, a protective cover, a motor and blades; a distance sensor is mounted on the protective cover and is connected with a controller, which is arranged above the machine body, through a wire; the controller is connected with the motor of the radiating fan through another wire. According to the water cooling and air cooling combined radiator with the distance sensing function, when a person gets close, the distance sensor senses a signal, and the signal is transmitted to the controller to control the motor to stop working and then control the rotation of the blades, so that working personnel are prevented from being hurt by the blades of the radiating fan.