(written from a Production point of view)
This is a list of performers who were considered for Star Trek: Discovery roles, but who ultimately did not appear in the final version of the series. Performers listed here have been verified as having been considered by Star Trek personnel for a particular role in which they ultimately did not appear.
|Performers considered for Star Trek roles|
|The Original Series • Films • The Next Generation • Deep Space Nine • Voyager • Enterprise • Discovery|
During a television appearance on the BBC with Jason Isaacs and Sonequa Martin-Green in early November 2017, Adams claimed that he had received a call about a month earlier whether he would come to Toronto, the series' shooting location, but "then it went away". Adams joked he looked "like a Klingon anyway." 
Prior to his past involvement with creating the series, former showrunner Bryan Fuller imagined ideally that "I want Angela Bassett to be the captain, that's who I would love to have, you know Captain Angela Bassett and First Officer Rosario Dawson." He added, "I would love to do that version of the show [...] but that's in the future to be told."  Regarding his interest in Bassett for the fledgling series, she responded, "That's thrilling, that's very nice, but how am I going to do that and American Horror? How is that going to work? ... Oh my gosh, and raise twins?" 
- Main article: Michael Dorn
Michael Dorn (born 9 December 1952; age 67) played Worf in some of the previous films and television series (as well as his grandfather in Star Trek VI: The Undiscovered Country), and had "a couple of conversations with producers" over the course of a couple weeks in the summer of 2016 for a possible role on Discovery. The discussions were eventually unfruitful, and, as of April 2017, there were "no plans for him to appear at this time" in the series. During a Q&A with the audience following an interview with Jim Helsinger, the Artistic Director for Florida's Orlando Shakespeare Theater, Dorn stated that he would appear as another Worf ancestor in a guest role in "the first episodes of the new series [that would] center around the Klingons." Rumors indicate that he ultimately turned down the role because he would have received low pay for his appearance. 
- Main article: Tony Todd
Tony Todd (born 4 December 1954; age 65), who appeared as Kurn, an adult Jake Sisko, and a Hirogen, expressed interest about working on the new series and even confirmed he was on a casting list of the studio.