Abstract : Stepper motors are high-precision motors widely used in industry. This paper briefly introduces the working principle and control principles of stepper motors, and then presents a design method for controlling stepper motors using a programmable logic controller (PLC). The hardware and software design methods of the control system are given. Practical applications demonstrate the effectiveness of the design. Keywords : Programmable logic controller; Stepper motor; Motor control 1 Introduction A stepper motor is an actuator that converts electrical pulse signals into linear or angular displacement. The output displacement of a stepper motor is proportional to the number of input pulses, its speed is proportional to the number of input pulses per unit time (i.e., pulse frequency), and its direction of rotation is related to the phase sequence of the pulses distributed to the windings of the stepper motor. Therefore, by controlling the number and frequency of command pulses and the phase sequence of the motor windings, the output displacement, speed, and direction of rotation of the stepper motor can be controlled. This gives stepper motors characteristics such as low rotor inertia, high positioning accuracy, no cumulative error, and simple control, making them one of the main actuators in the field of motion control. Stepper motors are key products in mechatronics and are widely used in various automated control systems and mechatronic equipment. With the development of microelectronics and computer technology, the demand for stepper motors is increasing daily, and they will be widely used in the control fields of various industries. Programmable Logic Controllers (PLCs) are industrial control computers with modular structure, flexible configuration, high-speed processing, precise data processing capabilities, multiple control functions, network technology, and excellent cost performance. They can fully adapt to industrial environments, are simple to understand, easy to operate, and highly reliable, making them one of the most widely used control devices [1,2]. PLCs also have good control capabilities for stepper motors. By utilizing their high-speed pulse output function or motion control function, stepper motor control can be achieved. When using a PLC to control a stepper motor, the pulse distribution can be implemented by software or by hardware. In this paper, we will introduce the design and research of stepper motors using PLCs. Taking Mitsubishi's FX2 series PLC as an example, we will discuss the hardware and software design methods of the PLC control system for stepper motors. [align=center][b]For details, please click: Research on PLC-Controlled Stepper Motor Design[/b][/align]