The calibration accuracy of multi-line structured light measurement s ystem directly affects the accuracy of measurement results.However,the traditional calibration method has the shor tcomings of too complex calibration model and too much calculation.At the same time,the traditional ca libration method is difficult to apply directly in the process of structured light measurement for the inner surf ace geometry of deep hole parts due to the lack of feature points.Therefore,a direct calibration method based on c alibration module is proposed,which can accomplish the calibration task directly by looking up the index table witho ut establishing the calibration model.The experimental results show that the calibration error of this method i s less than a single pixel,i.e. 0.037mm,which can meet the accuracy requirements of the measurement system and is easy to operate and realize.