PURPOSE: To obtain a rotary machine abnormality monitoring device which can be used inexpensively for a single or a small-scale rotary machine unit, at the same time can instantly monitor various kinds of failures of the rotary machine unit, and can cope with a number of rotary units with a single device.

CONSTITUTION: The device consists of a sensor 20 mounted to a rotary machine unit 10 to be measured, an amplification unit 40 for amplifying the signal of the sensor 20, a CPU unit 50 for performing A/D conversion of the output signal of the amplification unit 40, a signal reception unit 60 for receiving the signal from the CPU unit 50, and display lamps 70 and 71 which light up to indicate that the output signal of the signal reception unit 60 reaches an alarm level.