In order to study the friction characteristics of the spherical plain bearings of the civil aircraft high lift devices, a test equipment for friction performance of spherical plain bearings was proposed. The structural characteristics of the test equipment and the measuring principle of friction torque were introduced. A self-lubricating spherical plain bearing with a structure similar to that of the spherical plain bearing used in the high lift device was used in the test. The starting friction torques of self-lubricating spherical plain bearings were tested by this test equipment, and the friction torques of different types of self-lubricating spherical plain bearings under different rotational speeds, swing angles and radial loads were tested. The influence of these factors on the friction performance of the self-lubricating spherical plain bearings was analyzed. The results show that the speed in the low speed range has little effect on the friction performance of self-lubricating spherical plain bearing, and the equivalent friction coefficient decreases with the increase of load, and increases with the increase of swing angle and bearing size.