A new method that decreases the power loss in uplink propagation of a relay mirror system by using a Gaussian-vortex beam source is proposed. Performance of a 30 km-altituide relay mirror system that uses a Gaussian beam source is calculated. Results show that power coupling efficiency of uplink propagation in the relay mirror system is 76.48％, beam blocked by secondary mirror of the receiving telescope causes the main power loss and power loss proportion caused by beam blocking is 22.85％. Relation between shape and aperture of the dark area generated at the center of a Gaussian-vortex beam with parameters of the beam are analyzed in detail. Results show that shape of the hollow area is determined by amount of phase vortex of the beam, the hollow area is circular only when amount of phase vortex is times of 2π, aperture of the dark hollow increases with the increase of amount of phase vortex and propagation distance, respectively. Performance of a 30 km-altituide relay mirror system that uses a Gaussian-vortex beam source is calculated. Results show that power coupling efficiency of uplink propagation in the relay mirror system is 97.25％, and power loss in uplink propagation is significantly decreased.