The upper chamber approved the Trump's pick in a vote of 59-34, Xinhua reported.
"One of my top priorities is achieving President Trump's mandate from the American people to secure our southern border and fix our broken immigration system," said Noem.
Prior to her new capacity, Noem served as South Dakota's 33rd Governor and its first female governor. Noem served in the South Dakota legislature for years and was later elected to the US House of Representatives.
She is the fourth individual confirmed to join Trump's cabinet, after Secretary of State Marco Rubio, Central Intelligence Agency Director John Ratcliffe, and Pete Hegseth, who was narrowly approved as Secretary of Defense on Friday night.
Republicans currently have a 53-47 majority in the Senate. To confirm a presidential nomination, a simple majority is needed, meaning the Republicans can afford losing no more than two votes if all Democrats oppose the nomination.