The incident took place in village Hardoi of Bachhrawan region when following overnight rain, the roof of the house of Kishan Rahim collapsed early Friday morning, killing him and his three children.
Police said the house was in a dilapidated condition. Police personnel with the help of locals pulled out the bodies of the deceased from the rubble.
Rae Bareli is the parliamentary constituency of Congress president Sonia Gandhi.
Many parts of the state are experiencing heavy rain since Thursday night. The weather was unlikely to change over the weekend, met officials predict.