The traditional line laser scanning technology is based on machine vision, the corresponding algorithm is complex, the amount of calculation is large, and the matching efficiency is not high. In contrast, the point laser scanning technology is based on laser triangulation, the corresponding algorithm is concise, but the measurement speed is low and the reconstructed point cloud is sparse. To solve these problems, the laser-triangulation-based line laser scanning technology is proposed. The camera pinhole model and the relative position between camera and line laser are used for the establishment of an object-image relationship equation. The 3D coordinates of the scene are solved and the whole reconstruction algorithm is simplified. The calibration algorithm based on the least square method is adopted for the calibration of parameters such as the relative position between camera and line laser and the rotation center deviation of the system. Simultaneously, the theoretical precision of the system is analyzed, and the reliability and accuracy are tested by the experiments of scene reconstruction and accuracy evaluation. The experimental results show that the system possesses a high efficiency and a good precision. The error of the system is less than 2.6 mm and the precision is higher than 0.25% in the measurement range of 1000-1700 mm, which satisfies the requirements for a general scene reconstruction.