Microscale compressed air energy storage is not dependent on geographical environment, exhibits a flexible layout, and is especially suitable for distributed energy systems. Herein, a test bench of microscale compressed air energy storage is established. The effects of key parameters, such as regulated pressure, current, voltage, and rotating speed, on the output performance of a pneumatic motor (PM) and generator are examined. The power performance, economic performance, and energy efficiency of the PM in forward and reverse rotations are also investigated. The differences in the output performances of the PM and generator under the forward and reverse rotations of the PM are analyzed. Experimental results show that the PM's power performance, economy, and efficiency in forward rotation are greater than those in reverse rotation. The power output of the generator with the PM in forward rotation is greater than that in reverse rotation. The maximum values of the power output and efficiency and the minimum compressed air consumption rate of the PM are 650 W, 6.92%, and 0.165 g J−1, respectively. The maximum efficiency of the generator is 94.35%.