The Operation Anubis was a police operation in Catalonia, Spain, initiated on 20 September 2017 by the Civil Guard following orders of the trial court number 13 of Barcelona, directed by judge Juan Antonio Ramírez Sunyer. Its aim was to dismantle the framework of the Catalan independence referendum of 1 October 2017, that was suspended on 6 September 2017 by the Constitutional Court of Spain as breaching the 1978 Constitution. Different headquarters of the Generalitat de Catalunya were searched and 14 people were arrested, including high ranking administrative staff, and company CEO's involved in the preparation of the referendum. Simultaneously, several printing and media companies were searched looking for ballot papers and boxes. More than 140 websites were shut down by the Spanish justice and police.

The Civil Guard is the oldest law enforcement agency in Spain and is one of two national police forces. As a national gendarmerie force, it is military in nature and is responsible for civil policing under the authority of both the Ministry of the Interior and the Ministry of Defence. The role of the Ministry of Defence is limited except in times of war when the Ministry has exclusive authority. The corps is colloquially known as the benemérita. In annual surveys, it generally ranks as the national institution most valued by Spaniards, closely followed by other law enforcement agencies and the armed forces.