A man allegedly threw acid on his wife on Sunday after she refused to return to him at Kengeri near here, police said.
The couple had been married for 17 years and had four sons. The woman had been living separately for the past five years.
On Sunday, her husband, a painter by profession, asked her to come back and stay with him, but she refused, leading to a heated argument, they said.
Irked, the man threw acid on her, inflicting burn injuries on her face and back, police said, adding the woman has been admitted to a private hospitial.
The man has been arrested.