Electric field sensors have broad application prospects in the fields of automobiles, avionics, medical equipment, power systems, and high-energy physics research. They are also of great significance in the fields of engineering technology and scientific research. This study introduces several working principles of electric field sensors and provides a comparative analysis of the advantages of electric field sensors based on the lithium niobate electro-optic effect. The working principles of the integrated optical waveguide Mach-Zehnder structure and the microstructural electric field sensor based on resonance peak drift are derived. This study furthers summarizes and analyzes the recent research progress of electric field sensors of the lithium niobate bulk crystal type and thin-film lithium niobate type. The study also focuses on the improvement of sensor structure in sensitivity, linear dynamic range, frequency response, device size and other performance indicators and key technologies. The challenges and prospects for the future development of electric field sensors based on the lithium niobate electro-optic effect are also explored.