Speaking to the press, a BJP spokesperson said that the decision had been taken unanimously by all MLAs of the party.
Saha also took to Twitter to share the news and thanked the MLAs for choosing him to continue as CM.
"My sincere gratitude to all for electing me as the leader of legislature party. Under the guidance of Hon'ble PM Shri @narendramoi ji, we shall work together to build 'Unnata Tripura, Shrestha Tripura' & ensure the welfare of all sections of people," he said.
Earlier, there was speculation that Saha may make way for Union Minister Pratima Bhowmik to take up the top post in the state.
The swearing-in ceremony will be held on 8 March and will witness the presence of Prime Minister Narendra Modi, news agency PTI reported. Apart from Modi, BJP chief JP Nadda is also likely to be present on the occasion.
Assam Chief Minister Himanta Biswa Sarma had visited the state recently to discuss the formation of the next Cabinet.
In the recently held Tripura Assembly elections, the BJP won 32 seats in the 60-member House while its alliance partner, the Indigenous People's Front of Tripura, won one seat.