Abstract: Manual inspection is employed to identify defects in valve push rod for quality control, which has some unacceptable drawbacks such as inefficiency, susceptibility to undetected defect, and unreliability. In this work, eddy current testing based on electromagnetic induction principle is proposed to nondestructively evaluate the quality of valve push rods. The designed automated eddy current system consists of mechanical structure, electrical control and eddy current instrument. The valve push rods are able to be automatically loaded, transmitted, inspected and sorted in order through the developed system for quality examination. Subsequently, a finite element model is built to investigate the change of eddy current signals when the distance between the probe and the ball of a push rod increases. The signal analysis enables one to determine the non-detection zone of valve push rods. Finally, 100 valve push rods are selected randomly from the acceptable products through manual inspection, and five of them are identified to be defective. The results from the following manual inspection agree well with those from the developed automated eddy current system, which suggests that the developed system is superior in terms of efficiency and reliability.