The invention provides a single loop check valve test device. The device comprises a closed container, a test pump, a four-way valve and a check valve. The four-way valve has a first port, a second port, a third port and a fourth port. The outlet of the closed container and the first port form a first branch through a pipe. The second port and the third port form a second branch through the pipe.The fourth port and the inlet of the closed container form a third branch through the pipe. The test pump is arranged at the first branch. The check valve is arranged at the second branch. The first port and the fourth port are prohibited from being turned on. The second port and the third port are prohibited from being turned on. When the four-way valve is in the first switching position, the first port and the second port are turned on, and the third port and the fourth port are turned on. When the four-way valve is in the second switching position, the first port and the third port are turned on, and the second port and the fourth port are turned on. According to the single loop check valve test device, the water hammer effect when the check valve was closed is simulated by rapidly switching the four-way valve to change a flow direction of the medium, thereby testing the backflow shutoff characteristics of the check valve.