A method for measuring the size of a waterfowl body using a picture, comprising the following steps: 1) a picture scale calibration step 2) a picture body size measurement step and 3) a step of conversion between a picture measurement value of an individual body size and an actual measurement value of the individual body size. The beneficial effects of the present invention mainly lie in: 1, the measurement of the waterfowl body size data is more objective, and the diversity of measurement results caused by difference in measurement point cognition can be avoided by measuring the waterfowl body size using a picture 2, human resources are saved and 3, the body size measurement result is more accurate.
