Abstract: Objective This study aimed to reveal the quantity, morphology, and spatial composition of terrace damage and gravity erosion in a small watershed in the red soil hilly region after an extreme rainstorm, so as to provide a basis for post-disaster soil and water conservation investigation and restoration. Methods Taking the Huangshakengxi small watershed in Wuping County as the study area, UAV aerial photography and field verification were combined in September 2024 to investigate six terraced fields and 16 erosion patches. DEM and land-use data were overlaid for statistical analysis, and terrace damage and gravity erosion patches within the watershed were interpreted, verified, and statistically analyzed. Results A total of 508 gravity erosion patches were interpreted and identified, covering an area of 0.63 km² and accounting for 1.88% of the watershed area. Field verification showed that all 16 patches were shallow landslides, with planar shapes mostly fan-shaped or strip-shaped. The gravity erosion area distributed in the 5°～15° slope zone accounted for 66.40% of the total gravity erosion area, while this slope zone accounted for 59.24% of the watershed area. The gravity erosion area in forest land accounted for 82.06%, while forest land accounted for 83.57% of the watershed area. The terrace area was 192.15 ha, and the interpreted damaged area was 0.21 ha. Among the six typical terraces, the total length of terrace risers was 798.5 m, of which 52.0 m was damaged, with a length-based damage rate of 6.51%. No length-based damage was measured in the four terraces with drainage facilities, whereas collapse or landslide occurred in both terraces without drainage facilities. Conclusions Under extreme rainstorm conditions, terrace damage and gravity erosion such as shallow landslides coexisted in the red soil hilly small watershed, and were jointly influenced by drainage conditions, slope distribution, and land-use pattern. Therefore, post-disaster soil and water conservation work should incorporate both terrace engineering damage and gravity erosion patches into a coordinated investigation system and implement classified restoration measures.