Abstract: To clarify the morphological development characteristics of the ephemeral gully groove of different land use types under the "7·26" torrential rain on the Loess Plateau, and we took Chabagou watershed as the study area, which was a typical and representative region suffering from this extreme rain. The field investigation method was applied to study the morphological characteristics and erosion volume estimation of the ephemeral gully groove of three land uses (fallow land, farmland and abandoned land). A total of twelve typical small catchments in Chabagou watershed were selected to investigate the development characteristics of ephemeral gullies. The length of the ephemeral gully groove was measured with a laser rangefinder and a 50 m length tape. According to the length of the ephemeral gully, the cross-section was determined to measure the width of the top, the width of the bottom and the depth of the shallow trench with the steel tape, and the gradient of the slope was measured with the slope meter. The cross-section parameters (i.e. width and depth) of the ephemeral gully groove of all measured cross-sections were averaged as the values of the width and depth of each ephemeral gully groove, and the erosion volume of the ephemeral gully groove was the sum of the volume of all measuring sections. The results showed that: 1) the concentrated distribution range of width, depth and cross-section area of ephemeral gully in fallow land, farmland and abandoned land were 30-70 cm, 20-60 cm and 0.05-0.25 m2, respectively. On average, the width of ephemeral gully groove of fallow land, farmland and abandoned land were 46.46, 47.41 and 43.11 cm, respectively; the depths were 47.11 cm, 36.06 cm and 41.47 cm, respectively; the sectional areas were 0.23, 0.17 and 0.19 m2, respectively. Furthermore, the ephemeral gully groove depth and sectional area of fallow land were significantly higher than those of farmland (P<0.05). 2) The up-section of ephemeral gully groove of fallow land and farmland had the largest width-depth ratio, followed by down-section and middle-section, while for the abandoned land, the width-depth ratio followed the order of down-section > up-section > middle-section. The width-depth ratio for these three land types were all more than 1, which implied that the lateral erosion rate of the ephemeral gully groove was higher than the vertical incision rate. The ANOVA showed that the average width-depth ratio of the farmland was significantly higher than those of the fallow land and the abandoned land (P<0.05).3) The average erosion volumes of ephemeral gully of fallow land, farmland and abandoned land were 5.9, 3.26 and 4.5 m3, respectively, and the erosion volumes of fallow land and abandoned land are significantly higher than that of farmland (P<0.05). 4) The erosion volume of the ephemeral gully groove for the three land use types could be estimated utilizing the linear function, power function and exponential function of the ephemeral gully length. The results can provide scientific references for the prevention and control of ephemeral gully groove erosion under extreme rainstorm events.