A method for eliminating background noises in shear waves and the respective ultrasonic imaging system, the method includes: transmitting a push pulse along a push pulse vector； transmitting a first group of focus track pulses at a first group of a plurality of locations far away from the push pulse vector； receiving a first group of focus echo signals in response to the first group of focus track pulses； and processing the first group of focus echo signals to determine a first group of tissue displacement information varying with time.
