In this paper

we report the design and test of a wideband sensor for measuring transient electric field

which is consist of a monopole antenna

high input resistance receiving circuit

electro-optic modulating circuit and fiber links.In the end

a photoelectric conversion is conducted and the E-field signal can be watched on the oscilloscope.Test results show that it can satisfy time-domain and frequency-domain requirements.The sensor may play an important role in the EMP and EMC research.