Having excellent characteristics of nondestructive testing, noncontact measurement and etc., eddy current sensor is widely used in microdisplacement measurement, conducting medium defect detection and equipment operation condition monitoring in various industrial production fields. However, limited by the technical bottlenecks such as coil structure parameter optimization, detection circuit innovative design and measurement error dynamic compensation, the existing eddy current sensor generally has prominent limitations such as poor sensitivity, low linearity and being urgently improved detection precision under abrupt change temperature field, which directly restricts its popularization and application in the fields of highprecision detection under various extreme environments. Therefore, based on deeply analyzing and summarizing the research and application status of eddy current sensor both at home and abroad, this paper concentrates on the coil structure, detection circuit and error compensation method. The paper emphasizingly discusses the basic principles and key technologies for eddy current sensor core performance optimization, preliminarily outlines and forecasts the development trend of the related research, and hopefully provide effective reference for improving sensor performance in multiple dimensions and promoting its development and application.