Abstract: In this paper a digital beamforming technique for phased-array ultrasonic imaging equipment is proposed. In this beamformer, dynamic ultrasonic beam focusing along any steering direction can be achieved. Delay time for the received signal at each of the array elements is decomposed into two parts.One is accomplished by the same logic circuit to generate the transmitting pulse,the other is accomplished by using a "dynamic focusing delay time table).By coordinating the sampling chock,the addressing logic and the memory write operation, each sampled data is the necessary one for bearnforming, so that the buffer memory has no redundant data in it.The resulting electronic circuitry is simple and inexpensive.Preliminary experiment results show that the technique proposed is practical.