The vector hydrophone can measure the vector information of the water mass movement in the sound field. Among them, the pressure gradient vector hydrophone composed of two hydrophones is simple in structure and is suitable for low frequency detection. The modal analysis of the vibrator composed of beryllium copper alloy and piezoelectric ceramic disc is analyzed, and six bimorph hydrophones with good consistency are assembled as the vibrators of the pressure gradient vector hydrophone. The sensitivity and directivity of the pressure gradient vector hydrophone composed of bimorph and piezoelectric ceramic ring were calibrated. The results show that the sensitivity level of the pressure gradient vector hydrophone composed of the bimorph is 4 dB higher than that of the vector hydrophone composed of the piezoelectric ceramic ring，the directivity meets the cosine distribution and the engineering application requirements.