Three members of a family died by hanging themselves in Ghosipurwa locality, under the Shahpur police station of Gorakhpur district, police said on Wednesday.
The bodies of the man and his two daughters have been sent for post-mortem.
Police and the forensic team have collected evidence from the site.
In its initial inquiry, police personnel found that school fees of the daughters had not been paid for the last five months.
The school administration said both the girls were good students and due to their satisfactory education record, the school management had never put any pressure for fees.
Jitendra Srivastava, 45, lived with his two daughters, Manya, 16, student of Class 9 and Manvi, 14, student of Class 7. Both the girls were studying in a private English-medium school.
Srivastava had lost one leg in a train accident in 1999 and his wife, Simmi, had died of cancer two years ago.
Since the death of his wife, Srivastava had taken up tailoring in the house to earn livelihood. He was facing financial hardship from the last two years.
Gaurav Grover, SSP, Gorakhpur, said that Om Prakash, father of Jitendra Srivastava, who works as a guard in a private company, was on duty that night. When he returned home the next morning, he found all the three hanging and informed the police.