In order to improve the signal-to-noise ratio of the target axial frequency electric field, a coherent accumulation method combined with AR(autoregressive) model filtering was proposed to process the array electric field signal for the application scenario of using an array of electric field sensors to measure the electric field of a ship. The measured array electric field signal with time delay compensation was accumulated. The ambient electric field signal was AR modeled. By using the parameters of AR model, a filter was constructed to filter the accumulated signal. To verify the effectiveness of the proposed method under low signal-to-noise ratio conditions, the measured array electric field signals were processed. Results show that the proposed method can effectively suppress the noise spectrum and retain the axis frequency line spectrum under the condition of a signal-to-noise ratio of -25.39 dB. After keep the axial frequency line spectrum, the signal-to-noise ratio increased by about 21.92 dB.