Abstract: An animal ultrasonic mechanical arm automatic calibration method and system, including following steps: S1, constructing a target recognition model; S2, obtaining an initial ultrasound image and an initial white light image, determining a type of a target organ, and marking the determined target organ on the initial white light image; S3, obtaining an initial movement amount of the mechanical arm assembly; S4, the mechanical arm assembly moves a distance of the initial movement amount in a direction close to the detected animal; S5, using the steps S2-S3 to obtain a re-movement amount of the mechanical arm assembly when the mechanical arm assembly is located at the first movement position, and determining whether the mechanical arm assembly moves in the X direction, Y direction, and Z direction, when the mechanical arm assembly does not need to move, completing the calibration of the mechanical arm assembly, otherwise, iterating steps S4-S5.