Mr Wirepa said he was still coming to terms with the win.
"I was in shock when they read my name, I didn't even feel anything I just stood and shook everyone's hands. It still hasn't sunk in," he said.
The second-year design student won with his six-piece collection of evening wear called, "The Art of Fame". He used fabrics such as silk, satin, velvet and fur.
"I was inspired by all of the fabulous people here in Rotorua. We have singers like Sir Howard Morrison, Elizabeth Marvelly, [designers] Leilani Rickard and Adrienne Whitewood ... I've loved fashion since the day I was born. I've been brought up in an very artistic home."
Waiariki fashion tutor Julia Cass-Janes said they were proud of Mr Wirepa's achievement.
" ... we encourage all our students to enter competitions, especially our second-year students and Kharl definitely has the x-factor. He spends quite a bit of out-of-class time looking at the brief and his designs and styling - he's very dedicated."
Co-founder of Miromoda Maori Fashion Week Ata Te Kanawa said Dame Pieter thought Mr Wirepa was a talented designer but was also a talented stylist, which made him a stand-out.
Ms Whitewood won the established designer award in the competition which also featured work by fellow local designer Mereana Ngatai.
