Vectorial vortex beam possesses unique advantages in the fields of micro optical manipulation and optical communication. Rotational Doppler effect is usually applied in the researches of topological charges of optical vortex, and analysis of rotational Doppler effect of vectorial vortex beam is meaningful to deduce properties of polarization. Here a method to discriminate the direction of rotation of cylindrical vector beams is proposed based on rotational Doppler effect. In the method, the scattered light of an incident vectorial vortex beam carries beating signal whose intensity changes periodically with time due to Doppler frequency shift. The phase of the beating signal variation function depends on equator angle of vectorial vortex on high-order Poincaré sphere and the slope of the function depends on topological charge of optical vortex. The measurement theory of beating signals of two vectorial vortex beams with opposite handnesses are proposed and experimentally verified, which provides a new effective method to measure the signs of topological charges of cylindrical vector beams.