Kearney has been in sensational form for his province throughout the season and has become the bookies' firm favourite to wear the No15 shirt when the Lions take on the Wallabies next summer.
The 26-year-old featured in two Tests on his first Lions tour to South Africa three years ago and scored the opening try in the thrilling second international against the Springboks in Pretoria.
Kearney returned from the Republic with his reputation hugely enhanced but his stock has never been as high as it is right now, just 12 months out from the trip to Australia.
"This is a massively proud moment for me," said Kearney, who played a pivotal role in Leinster's record-breaking 42-14 win over Ulster at Twickenham on Saturday.
"To be recognised for your performances throughout the season is a dream come true, especially when it's in a European context.
"It's been a huge season for me especially given that I missed out on last year's Heineken Cup Final because of injury and had to watch from the sideline. So this time, I desperately wanted to be a part of it."
But while it was Kearney who was adjudged to have been his side's most valuable player during their charge to a third Heineken Cup title in four years, he was quick to praise the rest of a Leinster squad that includes the likes of fellow Lions Brian O'Driscoll, Gordon D'Arcy and Jamie Heaslip, as well as Lions hopefuls Sean O'Brien and Jonny Sexton.
"While I'm delighted with the recognition, an individual player is powerless without the support of his team-mates. So I owe this award to the Leinster squad, to the management and to the all staff at the club," added Kearney.
"To follow in the footsteps of Sean O'Brien as ERC European Player of the Year is really satisfying. Sean was phenomenal last season, and he was one of the main reasons why we won the tournament.
"Obviously, to win the Heineken Cup two years in a row is really special, but the Leinster squad and management are hungry for success and next season we'll be looking to win it again.
"We've reached four finals in two years, but it's important now that we don't lose the run of ourselves. We're constantly striving to improve, and as long as we stay in this place where the desire is there to keep on winning, then Leinster Rugby will be very strong for the coming years."