Indian National Lok Dal president Om Prakash Chautala expelled his two grandsons from the party's primary membership for "indiscipline", following dispute within the family.
The action comes days after Hisar lawmaker Dushyant Chautala and youth leader Digvijay Chautala, both sons of Mr Chautala's elder son Ajay Chautala, were suspended from the party.
"INLD MP Dushyant Chautala and Digvijay Chautala have been expelled from the primary membership of the party with immediate effect," a statement quoting Om Prakash Chautala said.
Dushyant Chautala is now no longer leader of the party's parliamentary board, it clarified.
Mr Chautala said it was not an easy decision as both are members of his immediate family. But all his life he has followed the ideals of former deputy prime minister Devi Lal for whom the party was always bigger than any family member, he said.
Making a choice between the party and members of his family, Mr Chautala said he decided to concur with the conclusions of the disciplinary committee.
Both Dushyant Chautala and Digvijay Chautala were accused of "indiscipline, hooliganism and spreading disaffection" after a ruckus at a rally in Gohana on October 7 to mark Devi Lal's birth anniversary.
Mr Chautala told his party that he did not need any evidence from outside as he was a witness to the unruly scenes in Gohana, where his own speech was also continuously interrupted.
But he still referred the matter to the committee which concluded that the two are "guilty" as charged, the statement said.
Om Prakash Chautala, who is serving a 10-year jail sentence in a teacher recruitment scam along with his elder son Ajay Chautala, attended the rally while on parole.
On being contacted, Digvijay Chautala claimed ignorance about the party's decision and said he had not received any official communication on the matter.
"I will be able to give a reaction once I receive the communication officially," he said over the phone.
The power struggle in the family surfaced when Mr Chautala dissolved the party's student and youth wings, headed by the two grandsons, following the disruptions at the Gohana meeting.
The disruption appeared to be targeted at Mr Chautala's younger son Abhay Chautala, the uncle of two sacked leaders.
Abhay Chautala has been running the party since 2013 after his father and brother were jailed.
Dabwali MLA and the mother of the two expelled leaders, Naina Chautala on Thursday alleged a conspiracy to throw her husband and their family out of the party.