Abstract: A measurement error compensation model based on the least squares curve fitting interpolation method is studied aiming at various detection errors of the existing contact probe in order to improve the efficiency and quality of CNC on-machine detection. The algorithm calibrates the probe model and constructs the system measurement error compensation model through the least square method, and designs a set of CNC wireless probe intelligent detection and control system with high accuracy to achieve the dimensional accuracy and error compensation of on-machine measuring parts. The production results show that the system error compensation algorithm is feasible, effective and superior, which improves the production efficiency and quality, reduces the defective rate and production costs, and can be widely applied to size measurement and error compensation of CNC milling precision machining parts.