The invention relates to a non-contact measurement method for the body size indexes of Xinjiang brown cattle. The method includes the following steps that a measurement system is arranged, wherein the measurement system comprises a measurement channel, five cameras, a host, a binocular camera calibration system and an image acquisition system, and the host comprises an image measurement system and a storage device; the measurement channel and the five cameras are installed, the binocular camera calibration system is controlled by the host to calibrate the five cameras, and a calibration result is stored in the storage device of the host; when a correct standing posture of Xinjiang brown cattle appears in the measurement channel, the host transmits a control signal to the image acquisition system, the five cameras are controlled to shoot images at the same time, image information shot by the five cameras is transmitted to the storage device in the host through the image acquisition system and named after the ear mark numbers of Xinjiang brown cattle, a measurement result is displayed and stored in the storage device after the image measurement system processes the image information, and measurement of the body size indexes of Xinjiang brown cattle is completed. The method is easy to implement, and measurement data is accurate.