An Interior Ministry statement today says the woman was arrested in the northeastern city of Figueres near Spain's border with France.
She was not identified and the statement did not say when she was arrested.
The statement says authorities started investigating the woman after combing through material seized from Ayoub Moutchou, a suspected Moroccan recruiter for the Islamic State.
Authorities say Moutchou fled Spain in July and was arrested in August in Stuttgart, Germany. Germany handed him over to Spanish authorities last week.