Adolescents who played a 3D fantasy game designed by mental health researchers had reduced symptoms of depression, anxiety and hopelessness.
Researchers from the University of Auckland in New Zealand said the intervention was as effective as usual care with a counsellor, psychologist or GP, but could offer a cheaper alternative.
In the trial, 187 adolescents with mild to moderate depression were randomised to receive usual therapy, or take part in the CBT game, 'SPARX'.
Researchers tracked depression scores at the start of the study and again after three months.
Results showed both groups reduced depression scores by the same amount.
Authors concluded SPARX is an 'effective resource for help seeking adolescents with depression at primary healthcare sites'.
They suggested the computer game could be considered as an alternative to usual care and used to address unmet demand for treatment.
It may also be a cheaper and more accessible alternative to standard care, they said.