The cell's suspected leader, Benaissa Laghmouchi Beghdadi, 42, recently returned to Spain from Syria and Mali before his arrest, a ministry spokesman said.
The arrests were made in Melilla, a Spanish enclave on the north coast of Morocco. The suspects are believed to have sent 26 Islamist militants -- 24 Moroccans and two Spaniards -- to terrorist groups in Syria, Mali and Libya, and have been flown to Madrid's National Police headquarters. They face arraignments Monday.
Spain, a gateway to Europe from North Africa, has been heavily involved in the capture of border-crossing terrorists. In January, a suspected Islamist militant was arrested in Malaga, Spain, as a potential threat to security, and a Spanish court convicted 14 militants for their roles in the 2004 bombing of Spanish commuter trains.
Spain has arrested at least 472 Islamic militants since the train bombings, and has over 1,800 security and police officials involved in anti-terrorism activities.
The arrests Friday came as an Interpol conference on terrorism, attended by 130 security experts from 33 countries, concluded in the Spanish city of Granada.