76-year-old Rashtrapal, a Congress member of the Upper House from Modi's home state Gujarat, died here this morning after suffering a massive heart attack.
"Pained by the demise of Rajya Sabha MP from Gujarat Shri Praveen Rashtrapal. My thoughts are with his family in this hour of grief," the Prime Minister said in a tweet.
"As a trade unionist & subsequently as a leader, Shri Rashtrapal remained sensitive to concerns & aspirations of the poor & marginalised," Modi added.
He was a elected to the 13th Lok Sabha (1999-2004). He was a member from the Upper House from April 2006 to April 2012 and was re-elected in April 2012.
Rashtrapal was a member of the Joint Parliamentary Committee on 2G scam in the previous Lok Sabha.
Following his demise, Rajya Sabha was adjourned for the day today.