Ong Hwee Keng was born in Muar, Johor, Malaysia and had his early education at Chung Hwa Primary School. He completed his secondary education in Muar High School and studied Agriculture at the University of Malaya. Upon graduation he worked as a research officer at the Malaysian Agricultural Research and Development Institute in Serdang, where he served for 38 years. While with the institute he obtained his M. Sc degree from Universiti Pertanian Malaysia and then did his Ph D at the University of Queensland Australia.. For his contribution to the institute he was awarded the Kesatria Mangku Negara (KMN) by the Yang Di Pertuan Agong of Malaysia in 2007.
Hwee Keng is married to Helen Yee Liang Jin and they have two sons, Evangel and Ernest. He is active in literature ministry, having written for Asian Notes and Asian Reflections produced by Scripture Union of Peninsular Malaysia.