The current measuring method of building basement is not effective in practical application, and its measured value is quite different from the actual value. In view of the shortcomings and defects, a measuring method for building basement based on 3D laser scanning technology is proposed. Through the three-dimensional laser scanning of the basement of the building, the basement space point cloud data is obtained, the statistical filtering algorithm is used to process the basement point cloud data filtering, the two-station registration method is used to process the basement point cloud data, the three-dimensional space model of the building basement is established, and the measurement of the building basement based on the three-dimensional laser scanning technology is realized. The test proves that the Pearson correlation coefficient of the design method is greater than 0.9, which can achieve accurate measurement of the basement of the building. The results can provide a certain reference for improvement in the efficiency and accuracy of basement measurements.