The invention discloses a unit efficiency tester. The unit efficiency tester comprises a wiring board, a signal conditioning plate, a power transmitter, a frequency transmitter, a power module and a data acquiring module, wherein the wiring board, the signal conditioning plate, the power transmitter, the frequency transmitter and the power module are connected to one another electrically; and the data acquiring module is electrically connected with the wiring board, the signal conditioning plate, the power transmitter, the frequency transmitter and the power module, and is connected and communicated with a testing computer through a serial port. By the data acquiring module, the testing data collecting and managing capability is improved; and the data acquiring module can be connected with the computer and is used for transmitting data. Compared with the existing tester, the unit efficiency tester is convenient to use. The invention also discloses a using method of the unit efficiency tester.