A method and device for selecting a detection area and an elasticity detection system, the method comprising: dividing organ tissue information to be identified into a plurality of detection sub-areas, and calculating a feature value of the organ tissue information within the detection sub-area (11) determining an organ tissue boundary area according to the organ tissue information to be identified (12) determining an organ tissue detection area according to the organ tissue boundary area and a preset feature value condition (13). The method determines an organ tissue boundary according to the organ tissue information, and automatically adjusts the detection area according to the organ tissue boundary.
