The sixth season of the American television series The Flash, which is based on the DC Comics character Barry Allen / Flash, premiered on The CW on October 8, 2019, and consist of 22 episodes. The season follows Barry, a crime scene investigator with superhuman speed who fights criminals, including others who have also gained superhuman abilities. It is set in the Arrowverse, sharing continuity with the other television series of the universe, and is a spin-off of Arrow. The season is produced by Berlanti Productions, Warner Bros. Television, and DC Entertainment, with Eric Wallace serving as showrunner.

The season was ordered in January 2019, and filming began that July. Grant Gustin stars as Barry, with principal cast members Candice Patton, Danielle Panabaker, Carlos Valdes, Hartley Sawyer, Danielle Nicolet, Tom Cavanagh, and Jesse L. Martin also returning from previous seasons, and are joined by LaMonica Garrett. Efrat Dor will appear as a series regular in the second half of the season.