[Objective] The relationship between rainfall intensity of different durations and regional landslide disasters was studied, and the meteorological warning threshold of landslide disasters was determined in order to provide a scientific basis of geological disaster warnings for local administrative departments. [Methods] Hourly rainfall data from 348 rainfall stations in the study area during 2013—2021 were collected, as well as the time and location of 231 disaster and dangerous landslide events that have occurred in the past 10 years. Based on the average rainfall intensity (I)—rainfall duration (D) model, the dataset was divided into geomorphic units. Critical rainfall warning thresholds were proposed, and graded warning thresholds for different rainfall durations were determined. [Results] Red warning thresholds for the average rainfall intensity at 1, 3, 6, 12, 24, and 48 hours under different early rainfall conditions in the hilly terrain area of the study area were 29.774, 18.579, 14.416, 11.186, 8.679 and 6.734 mm, respectively. The red warning thresholds for the average rainfall intensity at 1, 3, 6, 12, 24 and 48 hours under different early rainfall conditions in low mountain terrain areas were 28.849, 15.542, 10.520, 7.121, 4.820 and 3.263 mm, respectively. [Conclusion] Under the condition of rainfall in the early 24 hours period, the sensitivity of low mountainous areas to rainfall was significantly higher than the sensitivity of hilly areas. The critical warning thresholds at 1, 3, 6, 12 and 24 hours in low mountainous areas were significantly lower than those in hilly areas. However, with the further extension of rainfall duration, the critical warning thresholds at low mountainous areas and hilly areas tended to be similar.