The incident took place in Vijay Vihar area and the deceased has been identified as Shiv Kumar.
He was allegedly beaten to death by Harvinder, Sunil and Rakesh on Sunday night.
Kumar had lodged a complaint against Harvinder in 2011.
"Harvinder was nursing a grudge against Kumar. He invited Kumar to a party at his house. After consuming alcohol, the trio allegedly beat him up," police said.
Harvinder and Sunil were arrested this morning. Efforts are on to nab Rakesh.