Provided are a calibration method, device and storage medium of radiotherapy equipment. The calibration method of the radiotherapy equipment adopts an imaging body disposed within a preset distance range of an isocenter of radiotherapy equipment to perform error calibration on the radiotherapy equipment, and includes: imaging the imaging body through an imaging system to obtain an actual image of the imaging body； determining an image deviation between the actual image and a theoretical image of the imaging body, wherein the theoretical image is determined in advance based on a theoretical position of the imaging system and a spatial position of the imaging body in a rack； and determining a system error of imaging system based on the image deviation. Thus, the imaging system is calibrated without moving a treatment couch. The calibration accuracy of imaging system is not influenced by movement precision of treatment couch. The calibration accuracy is improved.
