Koul was born on January 6, 1937 in Srinagar, and did his graduation in Arts from Kashmir University and MA in Economics from Delhi School of Economics.
He started his career as a teacher with Rajasthan University and later resigned to join journalism in Kashmir Valley.
He joined Kashmir Post, one of the oldest tabloid newspaper in J&K and later Economic Times as Special Correspondent and reported for it from Jammu and Kashmir for two decades.
He also edited Kashmir Times, Daily Excelsior and Himalayan Mail as Editor for over two decades.
Koul was appointed as media advisor to J&K government during National Conference led Government headed by Dr Farooq Abdullah in 1986. He was also member of various economic panels in the state
He suffered a paralytic stroke in 2002 and was shifted to New Delhi for specialized treatment.
ON Koul was first elected president of Press Club of Jammu.