In response to the problems of the large workload of pipette calibration, low efficiency and errors introduced by manual long-term operation, the automatic adjustment system of pipette capacity is achieved by using a servo motor driven rotatable gripper to automatically adjust the capacity, together with machine vision as a tool to identify the pipette capacity value. More than 20 different types of pipettes are experimentally performed on automatic adjustment system, and the results show that the accuracy of the system can reach 100%, verifying the reliability of the system.