To address the problem of limited field of view measurement in traditional monocular vision measurement systems, we propose an omnidirectional spatial monocular vision measurement method based on a two-degree-of-freedom rotary platform. First, the rotating axis parameters of the double-degree-of-freedom rotary platform are calibrated. Then, the pictures of the checkerboard calibration plate fixed with the two-degree-of-freedom rotary platform are captured by using an auxiliary camera. Position coordinates of the checkerboard corner points are extracted and converted to the same camera coordinate system. The direction vector of the rotating axis parameters in the initial position is obtained through PCA (principal component analysis) plane fitting, and the position parameter of the rotating axis parameters in the initial position is determined using the method of spatial least squares circle fitting. The camera data acquired at various angles is transformed into the same coordinate system using the rotation angle of the rotary platform and the Rodrigues formula. This enables measurement of the target in the horizontal and vertical omnidirectional space. Finally, the measurement accuracy of the proposed method is verified using a high-precision laser rangefinder. Additionally, experiments comparing the omnidirectional spatial measurement ability of the proposed method with the binocular vision measurement system and wMPS measurement system are conducted. The results indicate that the method achieves a measurement accuracy comparable to that of a binocular vision system. However, it also surpasses the binocular vision system in term of measurement range, making it applicable for omnidirectional spatial measurements.