WRU National League rugby will be played at the ground when the RGC 1404 north Wales representative team joins Division One East from season 2012/13.
RGC 1404 is the team chosen to spearhead the WRU's initiative to drive forward and develop representative rugby in north Wales.
The WRU has granted development regional status to north Wales in order to target the area with specific resources and initiatives aimed at creating a team aligned to the union's elite player pathway.
Parc Eirias has been designated as the home of RGC 1404 and the WRU National Academy in north Wales is also based at the centre.
The high standards in facilities, installed as part of the £6.5m upgrade of the park, are aligned to the level required to deliver elite rugby performance.
The WRU Head of Rugby, Joe Lydon, said: "The opening of the Parc Eirias centre is a major landmark for our plans to develop the game in north Wales.
"Facilities of this standard are vital to help young players achieve their full potential through our player development pathway system. The fantastic facilities at Parc Eirias are without doubt both inspirational and aspirational.
"RGC 1404 now has the resources in place for a top quality home playing and training base and a real opportunity of making an impact in Welsh domestic rugby.
"We have always recognised the importance of north Wales rugby and today we can take satisfaction from the knowledge that, while there is much work to be done, the WRU strategic commitment has led to a real breakthrough.
"The facilities at Parc Eirias are excellent and north Wales now has a sporting complex it can be truly proud of."
The Group Chief Executive of the WRU, Roger Lewis, said: "Parc Eirias is a great facility which the people of north Wales can be truly proud of.
"The official opening of this facility is a catalyst for us to renew our efforts to drive rugby forward in the north.
"We now have the best facilities available, support from the National Academy structure and a team which will have an opportunity to improve and develop through our competitive league structure.
"I applaud Conwy council for their vision and the WRU's Head of Rugby, Joe Lydon for driving this forward.
"The Welsh Government has also played a key role in helping turn the dream of so many hard working people into a reality and I sincerely thank them.
"And so, I am delighted to announce today that our three Under 20's International matches in next year's RBS 6 Nations tournament against Scotland, Italy and France will all be played in Parc Eirias and will be broadcast live on S4C and BBC Wales."
WRU Chairman David Pickering said: "Parc Eirias is now a symbol of the sporting ambitions of the people of north Wales.
"The facilities are excellent and the region will undoubtedly reap the reward as more young people will now be able to achieve their true sporting potential.
"The WRU has worked hard to establish a formula which will give talented young rugby players from the north a chance to compete at the highest levels and Parc Eirias will play a key role in that process.
"Rugby will be a shop window for the wider sporting facilities at Parc Eirias and we are determined to utilise this facility as fully as possible."
The WRU is committed to providing further support to Conwy County Borough Council to stage events and generate rugby in the area.
A General Manager of RGC 1404 is being appointed to drive the project forward and maximise commercial opportunities related to the team.
Two more district Under 15 squads are being established and will compete in the famous Dewar Shield tournament to increase the critical mass of players in north Wales vying for selection into the WRU North Wales Academy.
WRU board member Gerald Davies said: "How wonderful it is that this progress has been made in north Wales.
"Such a development is long overdue and will do wonders for the development of rugby in the region and to the benefit of Welsh rugby as a whole.
"We have someone like George North who is a guiding light to all the talent in north Wales showing everyone just what is possible and this new development should ensure that more and more young people are able to follow in his footsteps."