On the basis of analyzing the current methods for large spacing axes detection at home and abroad, a method of axial consistency detection based on non-cooperative target image processing technology is proposed, which selects scenes with typical features in far field as non-cooperative targets arbitrarily, utilizes different optical sensors to acquire non-cooperative target images, and obtains axial consistency detection results by comparing the spatial position differences of non-cooperative targets in images. Experimental results show that this method can meet requirement of large spacing axis consistency detection. While the CCD imaging system is reliably clamped on the mechanical axis of the target to be detected, the consistency detection between the mechanical axis and the optical sensor axis can also be achieved. This method is not limited by the optical sensor's working band and avoids the disadvantages of large volume, heavy carrying and high requirements on environment for other detection methods, so it has broad application prospects.