Speaking at the launch, Philip Browne, the Chief Executive of the IRFU, said: "This is another significant partnership announcement for the IRFU and provides vital support to the future talent of Irish Rrgby.
"It is an indication of the strength of Irish rugby that it can attract and retain its association with one of the world's most recognisable brands.
"I would like to thank PwC for their support over the previous three years and hope that our partnership continues to see further successes."
Ronan Murphy, Senior Partner of PwC, said: "We are delighted to continue with our support for Irish rugby. No matter what the challenges in sport or in business, having the right team, with the right talent, will achieve top class performance.
"At PwC, we are committed to helping our clients tackle today's tough business challenges by having the best people working together.
"We wish the IRFU and the players continued success in the 2009 rugby season."