He is survived two sons and a daughter.
"He was in the hospital for the last 15 days. He was shifted to the ICU (Intensive Care Unit) yesterday (Thursday). He was suffering from chronic diseases," All India Institute of Medical Sciences (AIIMS) Director R.C. Deka told IANS.
"He was on life support," Deka added.
A staunch loyalist of the Gandhi family, Arjun Singh was twice the chief minister of Madhya Pradesh, governor of Punjab and commerce and human resource minister at the centre.
On Friday, Singh was named a permanent invitee to the Congress Working Committee.