The spatial mechanical structure deviation in cone-beam CT system cou ld introduce false image and significantly influence the measurement results,and they are difficult to be co mpletely removed from the measured data with the traditional calibration method.This paper presents a met hod for the measurement of angle parameters in cone-beam CT system due to structure deviations,which is b ased on space analytic geometry. With the single projection data of a calibration phantom,the measurement of ang le parameters can be realized. Both the computer simulation and experimental measurement have been carried out to validate the feasibility and accuracy of the proposed method.The results sho w that the proposed method provides a feasible way to measure the angle parameters of cone-beam CT system, and the measurement precision can reach the order of minute in the experimental validation.Compared with the measurement results with plane analytic geometry method,it can be demonstrated that the proposed me asurement method can separate angle parameters effectively.The proposed method for the measurement o f angle parameters of cone- beam CT system has high reliability and measurement efficiency,and does not nee d multiple projections.It has great practicality for angle parameters measurement and calibration of cone-bea m CT system.