In order to understand the changing law of frost date (number) in Jilin Province, and to improve the early warning and forecasting ability of frost disaster, Based on the day-by-day minimum temperature data from 47 meteorological observation stations in Jilin region from 1969 to 2020, the spatial and temporal distribution characteristics of frost date (number) were analyzed by using linear propensity ratio, Mann-Kendall method and sliding t-test, as well as REOF. The results show that: the first frost date, the last frost date, and the number of frost-free days follow the general spatial distribution pattern of "early in the northwest and late in the southeast," "late in the southeast and early in the northwest," and "long in the northwest and short in the southeast". The overall trend of frost dates is delayed first frost date, and early final frost date and prolonged frost-free days. The years with abrupt changes in the first frost date, final frost date and number of frost-free days were 2004, 1997 and 1991, respectively. The number of frost-free days in Jilin Province was categorized into 3 regions based on REOF analysis. It can be seen that analyzing the spatio-temporal variation rule of frost can provide theoretical basis for frost prevention and disaster reduction.