Abstract: In order to measure the electric field of electromagnetic pulse(EMP) with nanosecond rise time, a kind of broadband E-field sensor based on asymptotic conical antenna is proposed. The performance of the antenna is verified by modeling and simulation. An optical transmitter is designed to realize the electro-optical conversion and a fiber is used to transmit the signal. The output voltage of the sensor is integrated by Matlab. The performance of the sensor is tested by experiment. Research results show that this kind of measurement system has the characteristic of small size, good linearity, high noise immunity and wide-band response and it can be used to measure the E-field of EMP with nanosecond rise time. The development of the E-field sensor is of great significance for the measurement of EMP and further research on the characteristics and protection of EMP.