The Celtic League champions have sold more than 15,000 tickets for tonight's friendly match against London Wasps and are confident of beating Swansea City's stadium record of 16,733.
More than 3,000 tickets were sold on Tuesday alone after it was announced that Charlotte Church - girlfriend of Ospreys star Gavin Henson - would be singing before the game.
Ospreys managing director Mike Cuddy said: "We've had an absolutely phenomenal sales period over the last few days and to already have the highest-ever crowd in the history of regional rugby in Wales is amazing."
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.