He was 79.
Ray, who had been ailing for quite some time, breathed his last while undergoing treatment at a private hospital, family sources said.
A three-time MLA in Odisha assembly from Daspalla constituency, Ray had been elected to the Lok Sabha in 2009 from Kandhamal seat as a BJD candidate.
However, Ray who had long association with the Janata Dal and Biju Janata Dal joined BJP after being suspended from BJD in 2014.
Ray, regarded as an influential leader and good organiser, was associated with a number of activities in social, educational and cultural sectors.
Union Petroleum Minister Dharmendra Pradhan, Odisha BJP unit president Basanta Panda, senior BJP leader Bijay Mohapatra, Rourkela MLA Dillip Ray and State Parliamentary Affairs Minister Bikram Keshari Arukh expressed grief over his demise.