The fall happened in her office at the Supreme Court in Washington.
"She went home, but after experiencing discomfort overnight, went to George Washington University Hospital early this morning", the court said in a statement.
Ginsburg's hospitalization comes on the morning of the formal investiture of the court's newest justice, Brett M. Kavanaugh.
The next sitting of the Supreme Court begins on November 26, and Ginsburg's history suggests the injuries are not likely to keep her away. The hospital determined that "fractured three ribs on her left side".
But she has never missed Supreme Court arguments. Updates will be provided as they become available.
Asked a year ago if she was contemplating retirement, she said, "As long as I can do the job full steam, I will do it". "My senior colleague, Justice John Paul Stevens, he stepped down when he was 90, so think I have about at least five more years".
Should Ginsburg or any of the other three liberal justices step down while President Donald Trump is in office, that crucial advantage at the highest level of the judicial branch of the US government could grow even larger. "When I can't do the job full-steam".