For measurement of intensive power frequency electric field, an asymmetric optical waveguide MachZehnder interferometer based sensor was designed and fabricated with size of 80 mm × 18 mm × 7.5 mm. By tuning wavelength of the laser source, the drift of the working point caused by the environmental change can be compensated, and a static working point of π/2 is formed, which results the sensor working stably in the linear transmission point. An integrated electrooptic power frequency electric field sensor with shieling electrode was theoretically analyzed. According to the national standard GB/T127201991, a power frequency electric field test system was established, and the time domain dynamic range of the sensor was measured. Experiment results show that the sensor has a linear correlation coefficient of 0.997 from 0.35 kV/m to 125 kV/m, which is suitable for power frequency electric field measurement.