Amina was tipped to become UN deputy secretary-general after she led successful negotiations on the sustainable development goals
Guterres has made achieving gender parity at the world body a priority of his tenure, which begins January 1. Women currently fill less than one in four leadership positions at the United Nations.
A senior Brazilian foreign ministry official, Maria Luiza Ribeiro Viotti, will serve as Guterres's chief of staff, while Kyung-wha Kang of South Korea was appointed to the new position of special adviser on policy.
Amina Mohammed was widely tipped to become UN deputy secretary-general after she led successful negotiations on the sustainable development goals - 17 targets agreed by the United Nations to end extreme poverty by 2030.
The 55-year-old Mohammed will succeed Jan Eliasson of Sweden.
Viotti, who is Brazil's undersecretary for Asia and the Pacific, also served as ambassador to Germany and as UN envoy.
The 62-year-old economist helped shape Brazil's role within the BRICS club of emerging economies and worked as director for human rights in the foreign ministry.
Kang, 61, is currently head of Guterres's transition team and has served as deputy UN aid chief since April 2013.
Guterres, a former prime minister of Portugal who led the UN refugee agency for 10 years, won election as UN chief despite calls from civil society and some member-states for a woman to be chosen for the first time in the organization's 71-year history.
He said after taking the oath of office on Monday that "gender parity is a must" and "will become a clear priority from top to bottom in the UN."
Guterres will succeed former South Korean foreign minister Ban Ki-moon, who led the UN through two five-year terms.