The utility model discloses an apparatus used for measuring an engine. The apparatus used for measuring the engine comprises at least a supporting seat, a measuring instrument, a transmission shaft, and a display terminal, the measuring instrument is used for measuring performance parameters of the engine, the transmission shaft penetrates through the measuring instrument and the supporting seats in sequence and is connected with the engine in a rotating manner, and the display terminal is connected with the measuring instrument. According to the apparatus used for measuring the engine, the defect that in the prior art, in terms of small and medium-sized piston engines in the field of unmanned aerial vehicles, there is no apparatus specially for measuring the performance parameters so that safety accidents easily occur in the air flight operation process of the unmanned aerial vehicles is overcome.