There are wide application requirements for three-dimensional electric field sensors. In the presence of space charges in the surrounding environment, charges may accumulate at the surface of the electric field sensor, which is a key factor affecting the accuracy of electric field measurement. Especially for the MEMS three-dimensional electric field sensor, there is still a lack of relevant mechanism research and solutions. To solve this problem, an anti-charge-interference technology for the three-dimensional electric field sensor is studied. The effect of charge accumulated at the sensor surface on electric field measurement is studied, and the relationship between the interference of accumulated charge and size of the sensor structure is analyzed. The correctness of the theoretical analysis is evaluated by finite element simulation and experiment. On this basis, an anti-charge-interference method for the three-dimensional electric field sensor is proposed. By differential calculation of the signals from the sensing elements, the influence of surface charge accumulation on electric field measurement can be eliminated. An anti-charge-interference three-dimensional electric field sensor is developed. Experiments show that the measurement error is less than 4. 2% under the electric field of 0~ 30 kV/ m in the presence of charge accumulation interference.