The operational characteristics of miniature self-aligning ball bearing in a high-speed oscillating application are analyzed. Nonlinear static equilibrium equations of the bearing under radial load are set up and solved to obtain the properties indexes of the bearing， such as load distribution， support stiffness， rated load， oscillating working life， friction moment， etc. A test system of high-speed oscillating life for miniature self-aligning ball bearings is developed， which simulates the actual working conditions of high-speed swing and alternating load. In the test system， the crank shaper mechanism is used to implement high-speed oscillating condition， the flywheel is used to reduce the speed fluctuation of the mechanical system， the sine mechanism is used to achieve fluctuating radial load， the friction moment is monitored by measuring the tangential force， and the temperature of the bearing is observed by using infrared temperature sensor. The theoretical analysis and test system of the bearing described in this paper provide a basis for the determination of the working characteristics of miniature self-aligning ball bearing， as a reference for the research on other micro bearings.