During the milling process of a laser cutting machine, the surface may appear uneven or wavy due to workpiece deformation, with local areas of varying heights, resulting in the floating axis of the machine deviating from the actual motion trajectory and affecting the quality of workpiece milling processing. Therefore, a high-precision control technology for high-speed milling laser cutting machine tool CNC machining is proposed. Using kinematic theory and matrix transformation functions to establish a mathematical model of laser cutting machine tool motion, a high-speed milling control model of the laser cutting machine tool is constructed using PLC controllers, servo drivers, and motors. Negative feedback control algorithms and displacement error functions are used to control the floating axis motion of the machine tool milling process. That is, when the floating axis performs upward or downward floating motion, if the floating axis motion trajectory deviates from the preset trajectory, Adjust the parameters of the PLC controller to drive the motor to control the operation, causing it to move in reverse until it falls on the preset trajectory, achieving high-precision control of milling processing. The experimental results show that the milling quality of the proposed technology workpiece is high, and the maximum control errors of the upper and lower floating points during high-speed milling are 6 mm and 6 mm, respectively. The response time of milling control is 6.8 ms.