Underwater electric field is an important physical field that can be used for underwater target detection and recognition. Remote direction finding of underwater targets can be realized by an underwater electric field detection system with high sensitivity and low self-noise. Aiming at the underwater target direction finding problem,an underwater electric field direction finding method based on sparse Bayesian learning is proposed. The method uses multiple detection arrays to simultaneously collect and process the alternating electric field signal of the underwater target. Then,it estimates the signal direction of arrival(DOA)by the sparse Bayesian learning(SBL) algorithm. Finally,it estimates the relative orientation between the target and the detection system. The feasibility and robustness of the method are verified through lake tests. Compared with the conventional beamforming direction finding method,the direction finding accuracy of the sine wave electric field signal at 16Hz frequency is improved by 4.8° under certain test scene.