Star Trek: 10 Characters With The Most Appearances
4. 211- O'Brien
As one of the most important people in Starfleet history, Miles Edward O'Brien kept DS9 from turning into a mess of metal and circuits as part of the day job.
Sometimes though it's forgotten that O'Brien was right there from the beginning of TNG. While only referenced as Conn in Encounter at Farpoint, the chief was often seen just waiting around in the transporter room hoping that someone might need beaming up or down. Ok, a bit extreme to think he was just standing there for an entire duty shift, but it certainly led to more than a few memes and at least one notable comic strip.
Appearing as guest cast in 52 episodes of TNG, O'Brien would get married on the show and even have, unusually for this show, an entire episode focused on him with The Wounded.
After Rascals in season six he would transfer to DS9 as Chief of Operations, appearing in 160 episodes (not including those where he only appeared as Mirror Miles) and one as a holographic statue in Lower Decks Temporal Edict. Fans will also know that O'Brien popped up for a final appearance alongside the TNG crew for the pre-Farpoint scenes in the time-jumping finale All Good Things...