Abstract: Several models for sand deposit are given, including uniform particle calculation model-Durand formula and non-uniform particle calculation model-Kazanskij Formula, Shook Formula and Wang Keqin Formula. Prediction calculation for sand deposit is made by authors with a case of Nanpu 35-2 Oilfield WHPB-CEP submarine mixed transferring pipeline, and particle size analysis is performed for sand deposit with a laser particle sizer to verify the reliability of predicted results. The critical velocity for sand deposit is 1.931 m/s if it will be calculated as uniform particles, and the minimum critical velocity of sand deposit is 0.193 m/s if calculated as non-uniform particle, both of which are greater than the calculated 0.12 m/s-water-phase flowrate according to actual working conditions, showing that the problem of sand deposit will occur under current operation conditions for the submarine pipeline. The average particle size of deposited sand is 178.36 μm, far greater than 63 μm of corresponding hole size of sand filter mesh, showing the sand filtration mesh will be damaged due to wear and thus cause the increase of hole diameter for filtration. It puts forward the method for decreasing the risk of pig blocking and avoiding too much deposit of carrying sand.