The Senate voted 53-46, with all the Republicans backing Rao`s nomination and the Democrats opposing her confirmation.
The 45-year-old Indian-American, who serves as Trump`s "czar" overseeing regulatory rollbacks, was quizzed not only about her work in the Trump administration, but for her commentary she wrote in the past few years as a student at Yale University, when she opined that women should change their behaviour in order to avoid date rape.
While some Republicans had expressed apprehensions about her nomination, Rao apologised for her past writing last month.
"Sexual assault in all forms, including date rape, is abhorrent. Responsibility for the rape is with the rapist. I believed that as a college student and continue to believe that today. As a society, we should create an environment where survivors feel empowered and comfortable coming forward. I am sorry for anything in my college writings to the contrary," she wrote in a letter to the Senate Judiciary Committee.
Republicans expressed their gratitude to Senate Majority Leader Mitch McConnell for leading Rao`s confirmation process.
"Rao`s experience and intellect make her uniquely qualified to fill Justice Kavanaugh`s shoes on the DC Circuit Court of Appeals. Rao will fairly apply the law and honour the Constitution; she`ll be a phenomenal judge serving on one of our nation`s highest courts," said Judicial Crisis Network chief counsel and policy director Carrie Severino.
Born in 1973 in Detroit, Michigan to Indian immigrant parents - Zerin Rao and father Jehangir Narioshang Rao both Parsi physicians from India, Rao earned a one-year clerkship with Justice Clarence Thomas on the US Supreme Court.
She currently serves as the Administrator of the Office of Information and Regulatory Affairs (OIRA) of the Office of Management and Budget.
She has worked for the US government during the latter half of George W. Bush`s presidency and became a professor of law at George Mason University`s Antonin Scalia Law School.
Rao`s research and teaching focused on constitutional and administrative law, and she founded the school`s Center for the Study of the Administrative State.
Born in 1973 in Detroit, Michigan to Indian immigrant parents - Zerin Rao and father Jehangir Narioshang Rao both Parsi physicians from India, Neomi Rao earned a one-year clerkship with Justice Clarence Thomas on the US Supreme Court.