For a year, a team of scientists from the University of Melbourne and Murdoch Childrens Research Institute tracked 88 children aged 6-16, half of them with ADHD.
Their study involved using scratch and sniff tests of common smells such as orange, chocolate and pizza.
It was published in September's Journal of Clinical Psychiatry
Lead author Felicity Karsz, of the University of Melbourne's School of Behavioural Sciences and Department of Pediatrics, said a right nostril impairment appeared more evident among children with the disorder.
Similar problems of smell identification have been observed in neurodevelopment disorders such as Schizophrenia and Obsessive Compulsive Disorder, pointed out co-supervisor Professor Warrick Brewer of ORYGEN Youth Health Research Centre - Department of Psychiatry.
"The sense of smell is increasingly becoming a useful way to detect a vulnerability to a neuropsychiatric disorder," he says.
Prof Brewer says the findings could lead to a smell test which would act as screening tool for children with ADHD but would not replace current treatments.
Co-supervisor, Professor Vicki Anderson from the Murdoch Childrens Research Institute and the Royal Children's Hospital, says this information could supplement the well-established assessments for ADHD.
"There could be different reasons for exhibiting symptoms of hyperactivity and attention deficit and this area needs a range of strategies to confirm diagnosis and manage treatment," Prof Anderson says.