The differential equations of motion of the cloud droplets in wake vortices were derived. The trajectory and velocity distribution of cloud droplets in wake vortices were obtained by solving the equations of motion. Referring to the parameters of the typical W band millimeter-wave radar, the maximum detection range of wake vortex was analyzed. Then a methodology to simulate the radar Doppler characteristics of wake vortices in cloud was proposed, and the Doppler characteristics of wake vortices in cloud under typical resolution conditions were simulated. The simulation results show that Doppler characteristics of wake vortices in cloud are consistent with the velocity characteristics of wake vortices.