The Welsh Rugby Union has sent out invitations to every living former and current international asking them to attend at the Stadium.
The WRU will host an International Players Family Day where the stars of today and yesterday can meet up again with current and former team-mates.
It is part of a new initiative by the WRU to reunite the players and involve them in activities associated with the game in Wales.
The WRU President, Dennis Gethin, said:"The former players are jewels in the crown of Welsh rugby and it is right and proper that they are treated as guests of honour at special events.
"Winning a rugby cap for Wales is one of the greatest honours any Welsh sportsman can achieve.
"We have already hosted one inaugural event at the Stadium and it was a delight to see so many famous faces from the game gathered again in the home of Welsh rugby.
"These players are great ambassadors for Wales and great ambassadors for our sport and we will ensure they remain part of Welsh rugby even after their playing days are over."
Scores of former players have already responded to invitations sent out to their homes and the WRU is urging all who plan to attend to get in touch.
The players are being invited to bring along their families for a day of food and entertainment before the pitch is removed for the summer concerts in the close season.
A new database has been created by the WRU which holds details of all the surviving players who represented their country and a series of boards bearing the names of all former Welsh international players have now been installed in the tunnel where the team gathers before stepping out onto the pitch for international matches.
WRU International Manager Ann Hawkins has led the search for details of all former players and organised the May event.
She said: "These men are some of the nicest individuals it has been my pleasure to meet and we are rightly proud of them and their exploits on the field while representing their country.
"Some of them are now in their eighties but it is very clear that winning a cap for Wales has been a pivotal achievement in their lives.
"We want this to be a great family occasion and a relaxing social event which they can enjoy with their families and catch up with teammates some of them won't have seen for years.
"Lots of them are still associated with rugby and regularly attend events and games at the stadium but some of them have lost touch with the game since their playing days ended so it will be a wonderful chance for them to renew some old friendships."