The winner of the BT Young Scientist Exhibition said there are "no words in the English language to describe how" he feels.
15-year-old Simon Meehan from Coláiste Choilm in Ballincollig, Co.Cork was crowned the winner last night for his project about the medicinal use of plants to fight illnesses.
As well as the trophy and a cheque for €7,500, he will go on to represent Ireland at the EU Contest for Young Scientists in Dublin this September.
"My project is on the organic use of plants and how they may benefit is in the future and prevent antibiotic resistance," he said.
"I hope that it can mean survival, for example. There's so much that I hope to gain, not just me but for everyone, for every living thing," he added.
The group winners were Kerry students James Knoblauch, Harry Knoblauch and Oran O'Donoghue.
The 16-year-olds from St. Brendan's College in Killarney won for their project about "conformity and how minorities influence it".
They looked at how one person can influence the behaviour of others through a unique approach to studying group dynamics.