The invention discloses a signal amplifier detection device. The device is used for detecting a signal amplification function of a signal amplifier. A signal output circuit and a signal receiving circuit are built in the signal amplifier. The two circuits are mutually independent. The signal amplifier is equipped with a first wiring port and a second wiring port. The device comprises a power supply device which provides power for the signal amplifier; and a network analyzer which is equipped with two wiring ports, wherein the two wiring ports are respectively connected with two ports of the signal amplifier. Through utilization of the signal amplifier detection device, both an output signal of the signal amplifier and a receiving signal of the signal amplifier can be detected at the same time; detection is unnecessarily independently carried out at two times; and a detector can judge whether the function of a to-be-detected signal amplifier is qualified or not according to an observed result. Through utilization of the signal amplifier detection device, detection work processes can be reduced, and the working efficiency is improved.