According to police, Ashok Sharma was attacked at his home in Mukund Vihar and personal animosity is suspected to be the reason behind the attack.
Attackers barged into Sharma's house before shooting him in the chest, police said.
He was rushed to Guru Tegh Bahadur Hospital by his wife Sonia, but he was declared brought dead.
"Sharma was sleeping when unidentified men barged into the house and opened fire. He sustained a gunshot wound in his chest," a police officer said, adding an empty cartridge has been recovered from the house.