A dome has a round shape like grottoes,so it is the most appropriate solution for immersive display of the Mogao grottoes.However,it is difficult to capture the images of irregular shapes by camera.Mostly,the dome image is creating by rendering a high-precision digital model.How to create photorealistic high-precision grotto models is a big challenge.In this research,a laser scanner was used to establish a high-precision 3D grotto model in caves 196 and 285.Combined with high-resolution texture images,a realistic digital cave model can be created.A large dome image is achieved by rendering of this model with a virtual fish-eye lens.This approach proposed has been applied in the dome project of Dunhuang Academy.