This paper researches the sliding mode control (SMC) method for servo motor systems based on the gold rush optimizer (GRO). With the continuous progress of semiconductor chip manufacturing technology, higher requirements have been put forward for the accuracy and performance of packaging equipment. The servo motor mechanism plays an important role as a key component in semiconductor packaging equipment. SMC has been applied in multiple fields due to its strong robustness, but the manual adjustment of its parameters has brought great inconvenience to the research of practical application problems. This paper introduces the GRO to simplify the parameter adjustment process of SMC and improve the overall performance of servo motor system. Taking the voice coil motor as an example, the state space model is used to analyze its dynamic characteristics, and the sliding mode controller is derived and designed. The influence of different parameter choices on the controller performance is analyzed, and the GRO algorithm is used to optimize the parameters. The experimental results show that the sliding mode control method optimized by Gold Rush Optimizer (GRO-SMC) has fast response speed and high stability. It can quickly guide the servo motor system to the predetermined sliding surface, and the fluctuation amplitude of the system state is significantly reduced on the predetermined sliding surface.