The girl had eloped with the boy a few months ago and was later brought back to her parents, police said.
The parents of the girl said she was ill for some days and was under treatment and had died a natural death, police said adding that, they also showed medical prescriptions to police.
The body of the girl was recovered from her Kassaban house today and sent for post mortem examination.
Earlier, the parents of the girl had lodged a complaint that their daughter was missing and on their complaint police had recovered the girl from the boy's house and handed her over to her parents, police said.
The youth had filed a petition in the Allahabad High Court against the police action and the statement of the girl was to be recorded on February 27, it said.
The youth claimed that he had married the girl with mutual consent two months ago in an Arya Samaj temple at Kassaur in Kiratpur area.