The late night talk show host got real cornrows and a fake tan for last night's episode of the show -- looking just like a ginger Bo Derek.
"My audition for 'Jersey Shore' went really well, I aced that thing," he joked after walking out on stage.
We're guessing he won't be in the new cast of the MTV show ... so why did he do it?
Conan got his famous red hair done up as part of a promise to viewers. Last week, O'Brien said he would sport cornrows and a tan if his fans raised a lot of money for autism for the "Night of Too Many Stars" telethon.
While he said he was happy to do it for a good cause, the new look presents two problems.
"It hurts, it really hurts," Conan told Andy Richter ... adding that he also scheduled his family Christmas card portrait session for right after the haircut.