They surprised traffickers unloading the drugs from a six-engine speedboat before dawn on Sunday, and arrested one man.
The rocky Galician coastline, notoriously dangerous for ships, is a favourite entry route to Europe for cocaine traffickers.
A police spokesman said the cocaine would have a minimum street value of about 240 million euros ($320 million).
Over 117 tonnes of cocaine were seized in Europe in 2006, according to the European Monitoring Centre for Drugs and Drug Addiction, including some 50 tonnes seized in Spain.
Last Mod: 12 Ocak 2009, 15:29