Dr. Ong is a former student of Jit Sin High School, Bukit Mertajam. She graduated from Universiti Sains Malaysia in 2002 and subsequently obtained her MRCP (UK) and Master in Internal Medicine (National University of Singapore) in 2007 and then joined the Malaysian Ministry of Health Fellowship Training in Respiratory Medicine in 2008.
During her fellowship training, Dr. Ong underwent attachments at Cleveland Clinic, Ohio, USA in advanced diagnostic and therapeutic bronchoscopy, Sidney Kimmel Comprehensive Cancer Centre, John Hopkins Medical Centre, Baltimore, USA, Sleep Disorder Unit at Singapore General Hospital and Chang Gung Memorial Hospital, Taipei, Taiwan in pulmonary rehabilitation.
Dr. Ong is actively involved in a number of international clinical trials for non-small cell lung cancer (NSCLC) as a principal investigator. She also pursues her own research (investigator-initiated research) in her spare time. Her focus is on an important cohort study of 11 Asia-Pacific countries looking at the heterogeneity of COPD since 2009. She publishes and presents locally as well as internationally. She is also an Honorary Lecturer and Examiner at Penang Medical College and Penang International Dental College.