In this paper, particle analysis experiment, scanning electron microscope experiment, sand control experiment and permeability experiment were carried out for muddy fine sand reservoir. The sand control accuracy of gravel with different mesh sizes (30-50 mesh, 40-60 mesh, 50-70 mesh, 60-80 mesh, 70-90 mesh, etc.) was studied. The following conclusions can be drawn :(1) With the decrease of gravel sand retention accuracy, the degree of silty and argillaceous sand particles invading the sand control medium is weakened.The gravel with a sand retention accuracy less than 70 mesh is not suitable for sand control in the argillaceous silty sand reservoir. (2) For sand control media with blockage area ratio exceeding 47%, sand control and liquid production effects of gravel media with different sand retention accuracy are similar in the final stable state.(3) The gravel medium with a median particle size greater than 433μm or a permeability coefficient greater than 0.056cm/s will account for more than 47% of the blockage area. At this time, the effect of improving sand control accuracy to improve liquid production will gradually decrease. (4) The increase of sand control precision, the increase of liquid production and sand production in a short time, and the increase of damage degree of sand control medium. Among them, the 50-70 mesh sand control medium has stable permeability and relatively high steady liquid production, which is 87% of the maximum steady liquid production. The sand control medium has relatively low damage degree and relatively low sand production, which is 50.5% of the maximum damage degree, which is the optimal sand control accuracy under the condition of this reservoir.