In order to improve the performance of sand filter, explore the hydraulic characteristics of sprinkler sand filter and understand the special rules of water flow, effects of particle size and thickness on flow under sprinkler filter mode of saturated sand layer are studied through physical model experiment with quartz sand as filler, and relation curve and function expression are created. Results show that when the filter layer thickness is 0-4 cm, the water flow in sand filter increases from about 100 cm3/s to 600 cm3/s; the flow and thickness present a monotonic increasing relation, and the larger the particle size is, the faster the flow increases; the flow and particle size present a quadratic function increasing relation; when the thickness is above 40 cm, for sand filter with quartz sand of particle size 5-6 mm as filler, the flow is stabilized at about 410-420 cm3/s; for sand filter with quartz sand of particle size 7-8 mm as filler, the flow is stabilized at 640-650 cm3/s; for particle size of 1-2 mm and 3-4 mm, corresponding flow curves are close, and both increase with the thickness. When the thickness is constant, with increase of particle size of quartz sand, the flow in the filter also increases gradually, and corresponding flow curve at different thickness increases in parallel. The fitting curve of flow, particle size and thickness of sand filter obtained from the experiment may provide theoretical reference for the design and construction of sand filter and the selection of filter material.