In Thailand's resort of Pattaya, the contestants are part of a kissing marathon in an attempt to beat the current 32-hour record which was set in Germany last year.
The couples have each been given a space of one square metre and they must lock lips at all times, and cannot sit, sleep or leave the venue, or they will be disqualified.
One woman has fainted after 34 minutes of kissing. Others have given up after a few hours. The couple that last longest will receive a diamond ring worth £1,000 and a £2,000 cash prize, Metro says.
The couples began kissing at 11pm GMT on Saturday and have remained with locked lips without sitting nor sleeping ever since.
Competitors are allowed to eat, drink and use the lavatory, provided they do not break their embrace, Telegraph.co.uk reports.
Louis Tussaud's Waxworks-a Pattaya wax museum, is under the management of Ripley's World of Entertainment. Representatives of Guinness World Records were not immediately available to comment, but Somporn said they were aware of the contest.
The couples who took part were mainly Thai and ranged in age from 21 to 51. There was one German man with a Thai woman, and also a gay couple, according to Tri-Valley Herald.