As title?
I know a few have won belts in 2 weight classes at different times in their career but not sure about at same time?
Hendo in pride.
Nay
Not unless you count interim titles
Bone Tissa - Not unless you count interim titlesIf you do count them,who has?

guys like severn in the earliest days with tournaments and superfights
Uppercutz -ConorBone Tissa - Not unless you count interim titlesIf you do count them,who has?

TBH, the UFC didn't allow it back in the day. If Conor does so, it would be akin to Brian Taylor being the only guy to hit 90 3's in an NBA season, in 1979.
Miguel cro cop - Hendo in pride.Hendo held two UFC belts at the same time while in Pride? Interdasting.

I don't see how an interim title would count. Once the interim champ and the actual champ meet the interim title is retired.
stevekt - I don't see how an interim title would count. Once the interim champ and the actual champ meet the interim title is retired..

Answer....... no
Jon Jones was stripped of both the LHW belt and the interim LHW belt without ever losing either.. 2 title champ? Lol
Yes, as the first responder already pointed out, Dan Henderson was a world champion at 183lbs and 203lbs, at the same time. Then came to the UFC and tried to unify the titles w fights against Anderson Silva and Rampage Jackson
No. There have been multiple duel weight champions in other organisations but zero have done it in the UFC.
SidRival135 - Jon Jones was stripped of both the LHW belt and the interim LHW belt without ever losing either.. 2 title champ? Lol
I think the title earned there is criminal
AnotherDecision -LolSidRival135 - Jon Jones was stripped of both the LHW belt and the interim LHW belt without ever losing either.. 2 title champ? LolI think the title earned there is criminal

Elias Cepeda - Yes, as the first responder already pointed out, Dan Henderson was a world champion at 183lbs and 203lbs, at the same time. Then came to the UFC and tried to unify the titles w fights against Anderson Silva and Rampage JacksonIf we're using this logic, Mcgregor was LW and FW champion as well.

Randy and BJ won titles in dual weight classes but not at the same time.
I wish UFC would stop trying to be hard asses and just make Alvarez vs McGregor at MSG so we possibly could see someone finally do it.
Then after Connors next fight can be defending the FW title and then he can giver it up and focus on the killers row of LW challengers