Ginsburg officiated the marriage of Michael M. Kaiser, president of the John F. Kennedy Center for the Performing Arts, and John Roberts, an economist, NBC News reported. The ceremony took place in the Washington center's atrium.
Ginsburg and Kaiser are longtime friends, the network said.
A representative of the center said the wedding was "just a ceremony followed by a dinner" with more than 200 people attending.
Ginsburg, 80, voted with the majority in a Supreme Court ruling this summer that people in same-sex marriages are entitled to the same federal benefits enjoyed by heterosexual couples.
Thirteen states and the District of Columbia have legalized same-sex marriages, NBC noted.