The body of Surender, who lived with his sister in Akbarpur area of Vijay Nagar and ran a grocery shop nearby, was found hanging on the tree, a senior police officer said.
"Surender was to board Jharkhand-bound train early this morning and left his sister's house at 3.30 am. Around 8 am, his body was found hanging from a roadside tree on NH-24," the officer said.
Surender's relatives alleged that he had been murdered.
The body has been sent for post mortem, and the sister and brother-in-law are being interrogated to get some leads in the case, the officer said.
The sister's father-in-law is a sub-inspector with the Delhi Police.