In 2009, he was the legal advisor of
Songinokhairkhan District, one of the
9 municipal districts of Ulaanbaatar. From 2012 to 2016, he served as the chairman of the Citizens' Representatives Leaders' Khural in Songinokhairkhan. Nyambaatar, along with MPP MPs
Luvsannamsrain Oyun-Erdene, Tumurbaataryn Ayursaikhan, DP MP Luvsanvandangyn Bold, and
independent MP Jalbasurengiin Batzandan, joined the
popular demonstrations, boycotted parliamentary sessions, and submitted letters calling for speaker Enkhbold to resign. The cross-party group of politicians became informally known as the "Fair Five" (). Enkhbold would resign on 14 February 2019. Nyambaatar was re-elected to the State Great Khural from the same
municipal district in the
2020 parliamentary election. The MPP yet again won a
supermajority, where the party controlled 62 out of 76 seats in the State Great Khural. After the 2020 elections, he was appointed as the
Minister of Justice and Internal Affairs and a part of then-
Prime Minister Ukhnaagiin Khürelsükh's second cabinet, which lasted until the
January 2021 protests. Khürelsükh resigned after 2 days of protests, and was succeeded by Nyambaatar's long-time political ally
Luvsannamsrain Oyun-Erdene.
Mayor of Ulaanbaatar On 12 October 2023, Nyambaatar was appointed by prime minister Oyun-Erdene to become the 36th
Mayor of Ulaanbaatar after the previous mayor,
Dolgorsürengiin Sumyaabazar, resigned from his position due to a scandal involving the reform of the Ulaanbaatar
public transport fleet that was exposed as
embezzling public funds. Prior to the
2024 parliamentary election in May 2024, Nyambaatar was elected to succeed former mayor Sumyaabazar as the next Chairman of the Mongolian People’s Party of the Capital City during the Capital's
Party Congress. He was reappointed as Mayor of Ulaanbaatar after the MPP declared a decisive victory in the 2024 local elections, winning 40 of 45 seats in the
Citizens' Representatives Khural of the Capital City. ==References==