Based on the woman's complaint, a case has been registered at Chandni Mahal police station against Mohammad Shariq, who married her in 2008, they said.
The woman divorced Shariq in 2011 due to his drug addiction.
She now lives with her family in Chandni Mahal area and is getting married to another man in the coming days.
Yesterday, Shariq reached the woman's house with a bottle of acid and threatened her that if she went ahead with the marriage plan, he would pour the acid on her face.
"The woman's family immediately informed the police. The police reached there and nabbed him. He has served a jail term in Tihar Central Jail. We have arrested the accused and further investigation is on," said a senior police official.