The single-view point cloud obtained by the deep hole inner surface inspection system cannot reflect the full picture of the inner surface of the deep hole part. In order to realize the three-dimensional reconstruction of the complete surface shape of the deep hole inner surface, a pose calibration technology for the deep hole inner surface inspection system was proposed, which was used to provide the initial value of the point cloud stitching for the reconstruction of the inner surface of the deep hole. Firstly, the principle of deep hole inner surface detection technology was introduced, the coordinate transformation model of deep hole parts measurement point cloud was analyzed and established, the system pose parameters that need to be calibrated in the coordinate transformation model were determined; Then, the measurement trajectory of the system was described by the rotation axis angle, and the point cloud was reconstructed inversely; Then the measurement trajectory model was optimized with the solution error of the system parameter as the loss function, and the system pose parameter calibration was realized; Finally, point cloud splicing experiments of the straight cylinder and the concave groove show that the method was suitable for the detection of the inner surface of the deep hole and easy to operate, the splicing error was not more than 0.08 mm. Compared with other methods, it has certain advantages.