Dr Hatta Santoso Ong is a Consultant with the Department of Psychological Medicine at Changi General Hospital (CGH). He treats patients with mood and anxiety disorders, psychotic disorders, sleep disorders and addiction disorders. He is also part of the consult-liaison psychiatry team which treats mental disorders in patients with concomitant medical illnesses.

Dr Ong received his MBBS from the NUS Yong Loo Lin School of Medicine in 2011. He obtained his MRCPsych (UK) qualification from the Royal College of Psychiatrists in 2016 before subsequently completing his postgraduate training in psychiatry under the Residency Program.