An adaptive beamforming device belongs to medicine ultrasound imaging field. The invention provides an adaptive beamforming technique based on correlativity analysis, directing towards the difficultythat the traditional beamforming device can not completely restrain sidelobe effect resulted from interchannel random phase error and not affect the focusing effect along with the dynamic alignment ofdetection position. The technique divides the echo signal obtained from each channel into several segments, direct towards each segment, firstly the reference signal is obtained by a classical beam forming method, and then the signal of each channel is mutually correlated with the reference signal, furthermore weight of channel in each segment is dynamically adjusted using correlation coefficient, finally signals of each channel are synthesized to obtain final beam output using adjusted weight. The adaptive beamforming device adaptively detects the variance of enviroment using dynamic apodization and restrains the sidelobe effect resulted from interchannel random phase error. The adaptive beamforming device has wide application prospect in ultrasound imaging field.