Objective Aiming at the poor precision and great susceptibility to human factors in the process of sample pretreatment in modern food testing laboratories, an automatic pipetting device is developed to improve the detection efficiency and quality, reduce the cost of equipment and the complexity of maintenance, and meet the needs of dual-channel pipetting of various sample liquids between different specifications of test tubes.Methods The transmission structure of the screw driven by the motor is adopted to realize the accurate transverse and vertical movement of the screwing jaw and the pipette tip. A micro-upgrade precision suction pump is used to accurately absorb and release the sample liquid. On the basis of the YOLOv8 target detection algorithm, the upper computer of the pipetting control system is designed to realize the detection of the pipetting area and the initial positioning of the liquid level, and the execution units of the pipetting device are scheduled. The lower computer with STM32 single chip microcomputer as the control core is designed to connect with the upper computer through the network module to receive motion instructions and report the running state of each motor.Results An automatic pipetting device based on visual positioning is developed.Conclusion The device can complete the liquid transfer task with high precision according to the set procedure, and the test results meet the requirements of JJG 646—2006 standard, which can meet the liquid transfer requirements of sample pretreatment process in food testing.