Pema Khandu government of Arunachal Pradesh passed the floor test in assembly with 46 MLAs voting in favour of the Congress chief minister.
11 members from opposition BJP voted against it in 60-member House.
Khandu was elected as the new leader of Congress legislature party after Supreme Court restored the Congress government in the state.
Narendra Modi government had unconstitutionally dismissed the Congress government.
Last week, Khandu was sworn in as the ninth Chief Minister of Arunachal Pradesh marking the culmination of fast-paced political developments in this north-eastern state.
Chowna Mein was sworn in as the Deputy Chief Minister.
Congress on Saturday had played its master stroke to quell the rebellion, which posed danger to its government in the state on a day Nabam Tuki was asked to prove majority in the assembly.
Faced with a real possibility of a defeat, Nabam Tuki resigned the leader of the Congress Legislative Party paving the way for Pema Khandu, the son of former Arunachal CM, Dorjee Khandu, who had died in a chopper crash in May 2011.