Loess cave is closely related to other erosion processes,such as landslide and gully erosion,and aggravates the degree of soil and water loss in the loess plateau. However,the distribution characteristics and the erosion threshold of loess cave are not clear yet. This study uses unmanned aerial vehicle (UAV) to acquire the high resolution image and digital surface model (DSM) of the study area. Identifying the loess cave,collecting its land use type and measuring its average length based on image as well as extracting its terrain data such as slope,aspect,curvature and drainage area,we analyze the distribution characteristics of the loess cave. The results show that the average length of loess cave is mostly shorter than 4 m. The loess cave tends to develop in pasture area rather than in arable land and requires certain terrain,mostly develops in the concave slope with water converges. The number of loess caves that develop on shade slope is more than that on sunny slope. Also,the area exits loess cave is usually with the tangent value of slope between 0.4 to 1.0 and the drainage area less than 3 000 m². Drawing the erosion threshold of loess cave rely on the statistics data of the tangent value of slope and drainage area and comparing the erosion threshold of loess cave with that of shallow ephemeral gully and gully,the erosion threshold of loess cave can be applied as formulas SA^0.150=0.368 and SA^0.135=7.580,which is widely enough to cover the erosion threshold of shallow ephemeral gully and gully. The evolution of shallow ephemeral gully and gully is related to that of loess cave. The development and transformation of the shallow ephemeral gully and gully are promoted by the collapse and connection of the loess cave,thus aggravates the degree of soil and water loss in the loess plateau. This study quantifies the distribution characteristics of the loess cave and establishes the contact among loess cave,shallow ephemeral gully and gully. It deepens the understanding of the process of the loess cave.