The grottoes in the Sichuan and Chongqing area are mainly carved into cliff walls where alternating layers of sandstone and mudstone are exposed. The natural rock eaves in the upper part of the cliffs provide protection for the sculptures in the lower part. To assess the stability of these eaves under natural conditions, this study investigates the stratigraphic characteristics, rock mass structure, dimensions and mechanical parameters of the eaves. With using FLAC^3D for calculation and analysis, three main failure modes are identified: cantilever tensile failure, toppling failure and soft foundation crushing failure. The study also identifies the damage characteristics, key factors affecting eaves stability and their effects. A stability evaluation reference table is provided for field investigations and stability evaluation of grottoes eaves in the Sichuan and Chongqing area.