He was inspired to compete after watching Sophia Unga-Cribb compete and win both the regional and national section for her year level in the English section in last years Nga Manu Korero.
Sophia's mother asked Matariki Cribb-Fox who was a family friend of Kotuhi-Brown to help mentor him with and after spending some time with him she agreed.
"He's a hard grafter, he did the work, he memorised a 12-minute speech in a very short amount of time," she said.
Cribb-Fox said anyone who puts in the hard work and gets to the level of competition that Roman has, makes her proud.
He spent six weeks learning his speech and came out on top as the only Whanganui student in his year level to win, all three other sections were won by Taranaki students.
"I feel happy, proud and excited for nationals," he said.
Nationals will be held in Palmerston North on Septemeber 10-12 where Kotuhi-Brown will compete against 52 other junior speakers.
To celebrate his achievement, a powhiri was held on Monday at Whanganui High School to welcome Roman and his taonga, whanau and the Kapahaka group who supported him, back into school.