An electric field sensor（ EFS） with torsional resonance based on micro-electro-mechanical system（ MEMS） technology is proposed. For the first time

torsional resonance and coplanar electrodes are adopted

which leads to the increasement of the sensitivity. The working principle

structure design

finite element analysis（ FEA）simulation and experiments are introduced. Experimental results prove that the linearity is 0. 14 % in electric field range of 0 ～ 50 kV/m

and the total uncertainty is prior to 0. 43 % in three roundtrip measurements. The sensitivity reaches 4. 55 mV/（ kV/m） with gain-resistance of 100 MΩ

which is improved by at least one order of magnitude compared with previous available sensor.