Das was ill for quite some time, and after his health deteriorated, he was rushed to the Dr. B.R.A Institute Rotary Cancer Hospital at the All India Institute of Medical Sciences (AIIMS) on Monday, and put on life support system, his family sources said.
The BJD leader is survived by his wife and three sons, all of whom were present with him when he breathed his last.
His elder son Pranab Balabantaray is a BJD legislator.
According to sources, Kalpataru Das was undergoing treatment in Delhi and had earlier travelled to the US for consultation.
His body would be flown to Odisha on Sunday and the last rites would be performed in his native village, the sources added.
Born in Bhotaka village in Jajpur district, Das represented the Dharmasala assembly segment four times.
He was the panchayati raj and parliamentary affairs minister in Chief Minister Naveen Patnaik's cabinet from 2012 to 2014.
Das was elected to the Rajya Sabha on a BJD ticket in 2014.
Chief Minister Patnaik, state Congress president Prasad Harichandan, Leader of Opposition Narasingh Mishra, and state BJP president K.V. Singhdeo among others condoled the death.