Abstract: Based on the InVEST model, Assessment of habitat quality using GlobeLand30 land cover data for the third phase of Qinling-Daba Mountain, Shaanxi Province, The topographic gradient effect is studied by using topographic factors. The results show:(1)2000-2020, Land use change in Qinling-Daba Mountain area of Shaanxi Province is mainly cultivated land to construction land, and the mutual transformation between cultivated land, woodland and grassland; (2) The average habitat quality of Qinling-Daba Mountain area in Shaanxi Province in 2000,2010 and 2020 is 0.868 9,0.867 5 and 0.864 0, A sustained decline; 20 a, The area of high habitat remains stable, Large increases in the area of low habitats, Growth of 945 km²over the period 2000-2020 (3) The high habitat quality areas are mostly located around the Qinling Mountains in the northern part of the study area and the Dababa Mountains in the southern part, The lower habitat is mainly distributed in Xi'an, Hanzhong and Ankang three towns and surrounding areas; 2000-2020, The temporal and spatial evolution of habitat quality in Qinling-Daba Mountain area of Shaanxi Province is stable, The situation of local deterioration; (4) The distribution of habitat quality in Qinling-Daba Mountain area of Shaanxi Province has significant topographic gradient effect, Low habitats have strong distribution advantages over low topographic gradients, Higher habitats dominate the high gradient, The distribution of habitat quality is greatly affected by topography. Therefore, Depending on the topography of different habitat types, Proposing targeted biodiversity conservation measures, The results can provide theoretical reference for habitat protection and planning of Qinling-Daba biodiversity ecological function area in Shaanxi Province.