It was the 86-year-old justice's fourth bout with cancer since 1999, CNN reports.
SCOTUS Justice Ruth Bader Ginsburg completes radiation therapy to treat a tumor on her pancreas.
The Court says that there's no evidence of cancer elsewhere in the body, and no further treatment is needed at this time. In an interview last December, Ginsburg affirmed her commitment to remain a justice for "as long as I can do it full steam".
The court said in a statement that a biopsy performed July 31 at Sloan Kettering Cancer Center in NY confirmed a localized malignant tumour. The three-week, outpatient radiation treatment began August 5.
If Ginsburg, one of the nine-member court's four liberal justices, were unable to continue serving, Republican President Donald Trump could replace her with a conservative, further shifting the court to the right.
The court said Ms Ginsburg cancelled an annual summer visit to Santa Fe, but has otherwise maintained an active schedule during treatment.
She missed oral arguments for the first time earlier this year while recovering, but participated in rulings via court transcripts and in writing.
"The Justice tolerated treatment well", the statement said. The oldest Supreme Court justice, Ginsburg leads the liberal wing on the court which is now outnumbered 5-4 by conservatives.
The radiation therapy, conducted on an outpatient basis, began August 5, shortly after a localized cancerous tumor was discovered on Ginsburg's pancreas.
Ginsburg has become a liberal icon during her time on the court, known playfully as "Notorious RBG".
A bile duct stent was placed as part of her treatment. "That senator - whose name I've forgotten - is now himself dead". The Supreme Court justice was spotted shopping, going to the movies, attending the opera, and going to plays like, Fiddler on the Roof.
At the National Yiddish Theatre Folksbiene, where Fiddler on the Roof is playing, word spread during intermission that Ginsburg was there, and the audience stood for several minutes applauding the diminutive justice.
Ginsburg has 11 public events planned for September and has not canceled any of them to date. Trump has added two justices since becoming president in January 2017, cementing its 5-4 conservative majority.
She also said that people shouldn't try to set term limits for Supreme Court justices, an idea she repeated.