The Original Series (TOS)
* Leonard Nimoy (Spock) - February 27, 2015
* DeForest Kelley (Dr. McCoy) - June 11, 1999
* James Doohan (Scotty) - July 20, 2005
* Walter Koenig (Chekov) - May 18, 2022
* Nichelle Nichols (Uhura) - July 31, 2022
* George Takei (Sulu) - Still alive
* William Shatner (Kirk) - Still alive
The Next Generation (TNG)
* René Auberjonois (Odo) - December 8, 2019
* Jonathan Frakes (Riker) - Still alive
* Brent Spiner (Data) - Still alive
* LeVar Burton (Geordi La Forge) - Still alive
* Gates McFadden (Beverly Crusher) - Still alive
* Michael Dorn (Worf) - Still alive
* Marina Sirtis (Troi) - Still alive
* Patrick Stewart (Picard) - Still alive
* Colby Chester (Ro Laren) - Still alive
* Wil Wheaton (Wesley Crusher) - Still alive
Deep Space Nine (DS9)
* Armin Shimerman (Quark) - Still alive
* Cirroc Lofton (Jake Sisko) - Still alive
* Nana Visitor (Kira Nerys) - Still alive
* Avery Brooks (Sisko) - Still alive
* Alexander Siddig (Jadzia Dax) - Still alive
* Terry Farrell (Jadzia Dax) - Still alive
* René Auberjonois (Odo) - December 8, 2019
Voyager (VOY)
* Robert Beltran (Chakotay) - Still alive
* Kate Mulgrew (Janeway) - Still alive
* Jeri Ryan (Seven of Nine) - Still alive
* Ethan Phillips (Neelix) - Still alive
* Roxann Dawson (B'Elanna Torres) - Still alive
Enterprise (ENT)
* John Billingsley (Phlox) - Still alive
* Connor Trinneer (Trip Tucker) - Still alive
* Jolene Blalock (T'Pol) - Still alive
* Scott Bakula (Archer) - Still alive
This list only includes some of the most recognizable names and focuses on main cast members. Many other talented actors who appeared in guest roles or recurring parts have also passed away.
It's important to note that the world of Star Trek continues to grow and evolve, with new series and movies being produced. This list will continue to expand as time goes on.