Based on the theory of the solid-liquid two-phase flow, a solid-liquid stratified flow model is built to describe the performance of the sand moving by heavy oil in the horizontal wellbore, with overall consideration of influencing laws of sand shape on the particle settling velocity, and the sand concentration on the solid-liquid mixture viscosity. The influencing law of different sensitive parameters on sand-carrying capacity is summarized quantitatively by studying the model. The critical production values between the formation of the moving sand bed and the stationary sand bed under different sensitive parameters were quantitatively researched.