A novel swept flight terminal sensitive projectile was taken as a computation object, and the method to deal with simulation of the complex angular motion based on the Euler rotation theorem and a spherical sliding meshing technique was proposed. The modification value of the projectile′s angular velocity at each time step was interpolated out through applying the Rodriguez transformation matrix, and it was further allocated to the sliding meshing zone. Based on the method, the influences on pitching combination dynamic derivatives and lift coefficients under various Mach numbers made by the projectile′s rolling motion were analyzed after solving and identifying the unsteady aerodynamic parameters. Results indicate that: the proposed method can eliminate the accumulative errors in the calculation of attitude angles effectively and can realize the accurate simulation under arbitrary given angular motion; the projectile′s rolling motion generate significant influences on the identification results of pitching combination dynamic derivatives and lift coefficients, and the influence of the pitching coupled effect should be taken into account in the process of calculating the projectile′s pitching motion and stability analysis.