Yes! There are countless studies supporting the efficacy of masks.

The most influential evidence comes from studying respiratory droplets and the ability of various masks to block them. An experiment using high-speed video found that hundreds of droplets ranging from 20 to 500 micrometers were generated when saying a simple phrase, but that nearly all these droplets were blocked when the mouth was blocked by a face covering. Another study of people who had influenza found that wearing a surgical mask significantly reduces the amount of these respiratory viruses emitted in droplets and aerosols.