Parliament Chairman William Lukuvi on Tuesday announced Dr Ackson as winner.
Dr Ackson, who, until the election, was the Deputy Speaker, will be the second woman in Tanzania to serve as the National Assembly Speaker after Ms Anne Makinda, who held the position in 2010-2015.
Ackson, 45, a lawyer by profession, was deputy speaker under Ndugai.
She garnered all the 376 votes cast, beating eight challengers from other political parties.
The election to fill the position of deputy speaker seat that Ackson vacated earlier in the morning is set to be held later in the afternoon.
The election of the Speaker and deputy speaker was the first order of business as Parliament began its first session of 2022 in the administrative capital Dodoma.
Dr Ackson's triumph was widely considered to be a foregone conclusion after CCM's topmost decision-making organ, the Central Committee chaired by President Samia Suluhu Hassan, nominated her over several other party candidates and CCM legislators endorsed her at a caucus meeting.
The National Assembly is presently dominated by CCM by a big majority.
Of the 393 MPs currently registered, 362 are from CCM with just three other parties – Chadema, Civic United Front and ACT-Wazalendo – holding the remaining 31 seats.
Other aspirants for the position of Speaker who were voted out were Abdullah Mohammed Said of the NRA party, Aivan Jackson Maganza (TLP), David Daud Mwaijojele (CCK), Georges Gabriel Bussungu (ADA-TEA), Kunje Ngombale Mwiru (SAU), Maimuna Said Kassim (ADC), Ndonge Said Ndonge (AAFP) and Saidoun Abrahamani Khatib (DP).
Among the nine contenders, Dr Ackson was the only one who is currently a sitting MP.
Responding to questions from MPs while presenting herself prior to the vote, she pledged to restore public respect for the legislature as an independent pillar of the State and ensuring it fulfils its constitutional watchdog role over government performance.
