- Who
- Oleg Petrov, Anton Khantimirov, Mark Efremov , Nickolay Demyanov
- What
- 33/3/48.58 hour(s):minute(s):second(s)
- Where
- Russian Federation (Krasnoyarsk)
- When
The longest marathon playing Mahjong is 33 hr 3 min 48.58 sec and was achieved by Oleg Petrov, Anton Khantimirov, Mark Efremov and Nickolay Demyanov (all Russia) in the exhibition center "Sibir" in Krasnoyarsk, Russia, on 14-16 December 2012.