Kiran Bala, 38, was shot dead Saturday night in Khoda residential colony.
Police said she was sleeping with her five-year-old son when the assailants opened fire.
Kiran received bullet injuries in the head, police said. After killing Kiran, the assailants escaped.
The woman had married Mukesh Gurjar - a history sheeter - about 15 years ago. He is presently lodged in Tihar Jail.
"No arrest have been made. The dead body has been sent for autopsy," said city police chief Shiv Shankar Yadav.
Photos: Salman Khan returns from Jodhpur to Mumbai
15 'peach' perfect photos of Priyanka Chopra at People's Choice Awards 2017
Photos: Tennis legend Andre Agassi meets Rahul Dravid in Mumbai
62 going on 16: These photos of Rekha prove she is 'forever young'
Photos: 10 times 'Sultan' Salman Khan wrestled with the law