In her new position, she is expected to work closely with Stephen Miller, an anti-immigration zealot and Mr Trump’s deputy chief of staff, and Tom Homan, an unsparing former border force chief who has been installed as a new “immigration tsar”.
One of Mr Trump’s top campaign pledges was to conduct “mass deportations” of illegal immigrants in the US.
Among the raft of agencies Ms Noem will oversee is the Federal Emergency Management Agency (FEMA), which Mr Trump has suggested disbanding.
Ms Noem previously accused FEMA employees of “not showing up” following natural disasters, and said she would create a “blueprint” for how the agency should respond.
When asked at the hearing to address the distribution of disaster aid, Ms Noem said “there will be no political bias to how disaster relief is delivered to the American people.”
Ms Noem courted controversy last year after she revealed she had shot her family dog dead in her book.
The politician said she shot the 14-month-old wire-hair pointer named Cricket, in a gravel pit because the dog was “untrainable” and “dangerous to anyone she came in contact with.”
