Gov. Martin O'Malley signed a bill legalizing same-sex marriage earlier this year, and the law is go into effect in January, The Washington Post reported. However, a referendum to repeal the law appears on the November ballot.
But with the Court of Appeals ruling, the Post said, same-sex couples would still have the right to divorce.
The decision came in the case of Jessica Port and Virginia Anne Cowan, women in their 20s, who were married in California in 2008. They filed for divorce in Maryland's Prince George's County two years later.
A circuit judge refused to grant the divorce, saying it would be "contrary to the public policy of Maryland," the Post reported.
But the Court of Appeals unanimously overturned the circuit judge's ruling, saying "a valid out-of-state same-sex marriage should be treated by Maryland courts as worthy of divorce."