Police said the parents of the deceased couple, however, managed to escape.
The two-storey wooden house caught fire reportedly after it was struck by lightning during a thunderstorm and within minutes the entire house was engulfed in flames.
The couple -- Mahesh Kumar (27) and Hemlata (24) -- were sleeping on the upper storey, along with their daughters Deepa (4) and Jayati (2), when the fire took place, police said.
The fire broke out around midnight and fire tenders were rushed to the spot but the vehicles could not reach the house as it was not connected by motorable road and firemen had to trek about 1-km distance.
"We tried our best to reach the spot at the earliest but the wooden structure went up in flames within no time and there was nothing to salvage," a fire personnel said.
Meanwhile, a seven-year-old girl was injured at Bhatwar, 5 kms from Palampur, after she lost her balance and fell during a severe storm which hit Palampur last night. The girl was rushed to hospital with multiple injuries and was in a critical condition, police said.