Police said villagers noticed a board on the gate saying the trio had committed suicide and two dead dogs lying in the entrance.
When they went inside the house, villagers saw bodies of Vetrivel (50),his wife Lakshmi (45) and daughter Manjubharathi (25) hanging from the ceiling and informed police.
Police suspect that Vetrivel, a farmer, first ensured the death of the women before committing suicide. The dogs had been poisoned, they said.
Photographs and some documents were found burnt in the house and preliminary inquiries revealed that Vetrivel, a farmer, was plagued with financial burden which could have been the reason for the suicide.