Lok Janshakti Party MP from Bihar's Samastipur Ramchandra Paswan died on Sunday afternoon following brief illness.
He was 57 and the younger brother of Union minister and LJP chief Ram Vilas Paswan.
Party leader Chirag Paswan said his uncle breathed his last at 1.24 pm at the Ram Manohar Lohia Hospital in New Delhi.
Ramchandra Paswan was admitted to the hospital last week after suffering a heart attack.
His body will be kept at his residence in New Delhi and on Monday, at the LJP office in Patna for paying last respects.
He is survived by his wife, two sons and a daughter and will be cremated in the Bihar capital on Monday.
"With deep sorrow, I wish to inform that my uncle Ramchandra Paswan is no more. He breathed his last at 1.24 pm at Ram Manohar Lohia hospital in New Delhi," Chirag Paswan tweeted.
"The body Ramchandra Paswan ji will be kept at his residence at 18, Rajindra Prasad road from 5 pm onwards for paying last respects. The body will be taken to Patna, where it will be kept at Lok Janshakti Party's office there from 11 am to 3 pm for paying the last respects. He will be cremated at 4 pm in Patna," he said.
Ramchandra Paswan was a four-time MP and was first elected in 1999.
He was re-elected to the Lok Sabha in 2004 and then again for the third time in 2014.
In May 2019, he was again elected to the Lok Sabha from Samastipur in Bihar for the fourth time on a LJP ticket.