Abstract: In order to obtain the surface features information of the workpiece to be grinded, a method for surface detection of grinding workpiece based on laser scanning was proposed. The robotic arm was used to drive the laser sensor to scan the grinding workpiece placed in the laser measuring plane, thereby obtaining the three-dimensional coordinates information of the workpiece in the laser measuring plane, and obtaining the characteristic boundary point of the workpiece by the height change between two adjacent scanning points. Then, the extreme points and least squares of the x-axis and y-axis coordinates were combined to fit the analytical expression of the workpiece boundary in the laser measurement plane, and the offset and rotation angle of the workpiece relative to the laser measurement plane were further determined. Finally, the surface features information of the workpiece was obtained by using the position and attitude information of the workpiece in the laser measuring plane. The experimental results show that the detection error of the workpiece surface is 0.11 mm and the average detection time is within 1 s, which meets the requirements of workpiece surface features detection.