The utility model provides a laboratory rainfall simulation device, includes water collecting bottle, earth pillar bucket and graduated flask, and the earth pillar bucket includes two upper and lower openings, and water collecting bottle sets up on the opening of the upper portion of earth pillar bucket, is equipped with the graduated flask on the lower part opening of earth pillar bucket, be equipped with permeate water dish and water permeating cushion piece in the earth pillar bucket, set setting of permeating water in water permeating cushion piece top, is equipped with the hole of permeating water on the dish that permeates water, and both sides are equipped with a fixed column locating lever respectively about the dish that permeates water, are equipped with the location section on the fixed column locating lever, are equipped with the through -hole in the section of location, and the fixed column both ends are fixed respectively in the through -hole of two fixed column locating levers, and the fixed column is worn to establish on the dish that permeates water, and the dish that permeates water can be followed the fixed column and slided. Adopt above -mentioned structure, can simulate the more real rain condition of falling shape, guarantee the homogeneity of precipitation, avoid lasting the surperficial disturbance of soil that precipitation caused to same region, greatly reduced the experimental result error.