Uma Jha, from Perth's Shenton College, in inner-west Shenton Park, outsmarted more than 4000 competitors from across Australia to bag the title.
The 2010 Australian Brain Bee Challenge is designed to test high school students on a range of topics, including intelligence, memory, emotions, sleep, Alzheimer's disease and stroke.
Uma has to compete against other state winners in the national final of the competition, which included a brain-teasing anatomy exam, doctor-patient diagnosis and a neuroscience quiz.
"The competition was tied right up until the end and it was a really nerve-wracking finish," News.com.au quoted Uma as saying after the event.
"I've never won a national science competition before, so it's amazing," she added.
However the hard work does not stop here for Uma. She will now travel to California for the International Brain Bee Challenge in August. (ANI)