To explore the compression characteristics and failure precursor of phyllite, the acoustic emission (AE) test was carried out on the condition of uniaxial compression experiments. A self-programmed computer procedure is used to complete the filtering, time-frequency transform and data analysis of AE signals. The uniaxial compression process of phyllite can be divided into three stages: calm stage, active stage, and intense stage, which corresponds to the low-frequency band (40-198kHz), intermediate frequency band (198-232kHz), and high-frequency band (232-400kHz). The first and second dominant frequencies exhibit strong aggregation along with the sequence of AE. Low main frequency ratio corresponds to high main amplitude ratio, and vice versa. When approaching the failure stage, there is a sudden change in the main amplitude ratio, a decreasing change in main frequency ratio along with an aggregation state. There is good consistency between the compressive characteristics reflected by the stress-strain curve and the main frequency characteristics by the AE signal, highlighting the characterization of AE technology. The results of this experiment can provide a certain application reference for the precursor of instability or failure in the engineering of phyllite rock mass.