A father and daughter who lived as husband and wife and had a child together have been charged with committing incest.

The 32-year-old man and 18-year-old woman admitted the charge when they appeared in the Dunedin District Court on Friday, the Otago Daily Times reported.

The pair, who have lived together for about two years, have been in a sexual relationship since August 2010, which resulted in the birth of a child.

When police questioned the pair after receiving a complaint last month they freely admitted to living as husband and wife with the knowledge that they were father and daughter.

The woman said she was in love with the man.

The man fathered the woman when he was 14 and had little to do with her until she turned 16.

The father made contact with his daughter's family in 2010 and arranged to visit her. After several visits they began living together.