"My thoughts are with Shri R R Patil's family. (I) am saddened to know of his demise, which leaves a void in Maharashtra politics," Modi tweeted.
Patil died in Mumbai from cancer at the age of 57.
Patil, who was Maharashtra's Home Minister during the 26/11 terror attacks, breathed his last at Lilavati Hospital where he was on life support, hospital sources said.
The NCP leader, a six-term MLA from Tasgaon in Sangli district, is survived by his mother, wife, and two daughters.