"Sam is an exceptional player in either code of rugby and his selection shows the growing mutual respect between the codes of rugby league and rugby union in England,'' he said in a statement released by the game's organisers.
"It's a great opportunity for Sam to experience the Twickenham atmosphere and showcase his talents on another major stage.''
Barbarians' commercial director Mike Burton added: "The Barbarian club has a tradition of thinking outside the circle when inviting players with league backgrounds and usually to everyone's benefit.''
Their coach is recently retired New Zealand boss Graham Henry and the 22-man squad, drawn from 10 countries, share an astonishing 1000-plus Test caps.
The latest additions include Italy's Mauro Bergomasco (88 caps), Salvatore Perugini (83) and Marco Bortolami (88), France's Sylvain Marconnet (84), Scotland's Jason White (77) and Ireland's Peter Stringer (98).
They join a squad already boasting Springbok lock legend Victor Matfield (110) who, two years ago, captained the Barbarians to victory over the All Blacks.
Further additions are Fiji's Seru Rabeni and Nemia Kenatale.
Barbarians squad: Sam Tomkins (England RL), Bryan Habana (South Africa), Isaia Toeava (New Zealand), Robbie Fruean (Crusaders), Stirling Mortlock (Australia), Richard Kahui (New Zealand), Seru Rabeni (Fiji), Danny Cipriani (England), Peter Stringer (Ireland), Nemia Kenatale (Fiji), Keven Mealamu (New Zealand), Adriaan Strauss (South Africa), Salvatore Perugini (Italy), Sylvain Marconnet (France), Eusebio Guinazu (Argentina), Victor Matfield (South Africa), Simon Shaw (England), Marco Bortolami (Italy), Jason White (Scotland), Jerome Kaino (New Zealand), Adam Thomson (New Zealand), Mauro Bergamasco (Italy).
The captain will be announced when the squad assembles in London on 22 November.
- AAP