Laser spot center detection is widely used in vision-based deformation measurement system,so its detection algorithm directly affects the measurement accuracy of the system. The existing laser spot location algorithm has some problems such as low positioning accuracy and poor anti-interference ability. In order to achieve high-precision spot location,an improved laser spot center location algorithm is proposed. In this method,Fisher criterion function is applied to Otsu method for threshold segmentation of laser spot image,which reduces noise interference and improves laser spot location accuracy. Experiments show that compared with the traditional threshold segmentation method,the error of spot center location is reduced by more than 40 %.