Abstract: Dabieshan Mountain Area in Hubei Province is an important water supply area of the middle reaches of the Yangtze River, and the middle and lower reaches of the Huai River, as well as an important ecological barrier in the central region. The evaluation of water conservation function provides an important data basis for ecological protection and ecological planning. Take the Dabieshan Mountain Area in Hubei Province as a study object, the paper evaluates the water conservation with the water balance model using high-precision and fine ecosystem types data, and analyzes the impact of spatial distribution characteristics, ecosystem types, altitude, and slope on the water conservation function. The results show that: (1) the mean water conservation depth of the study area in 2020 was 292 mm, and the total water conservation was 43.57×108m³ , which showed it was powerful in the east and weak in the west from the space． (2) the forests and shrubs contributed 70% of the total water conservation; the evergreen broad-leaved forest and evergreen broad-leaved shrub had a better water conservation capacity per unit area, namely 620.63 mm and 539.51 mm respectively． (3) the total water conservation in the middle and lower altitude areas is 100-300 m, accounting for the largest proportion of 42.86%, and the water conservation capacity per unit area in the area of high altitude, namely 1 000-1 700 m was the highest, which was 711.79 mm; the gentle slope area is 5°-15°, making the greatest contribution for the total water conservation, which was 47.80%. (4) the extremely important areas for water conservation took up 6.56% of the total area, and they were mainly in the east, such as Jiuzihe Town, Wenquan Town and Qingshi Town; while the important areas of water conservation accounted for 12.08% of the study area, mainly concentrated in the mountainous areas of Caopandi Town, Shitouzui Town, Yingshan County and Jiuzihe Town, Luotian County in in the south of the study area. The results of this study can provide important data support for ecological environmental protection, ecological restoration planning and ecological space control in the Dabieshan Mountain Area of Hubei Province, and have great significance for promoting the construction of ecological civilization in Dabieshan Mountain Area of Hubei Province.