The raid took place during the recent high profile Pirate Bay trial. The server was located in the Brandbergen neighbourhood south of Stockholm and was part of a Nordic file sharing ring known as Sunnydale, according to the Swedish Anti-Piracy Agency (Antpiratbyrån), a private copyright advocacy group.
The confiscated computer contained data equivalent to 16,000 movies, making it the biggest ever seizure in the country, the agency said.
"The well-organized pirates on the scene seem to have an inflated sense of their own ability to conceal themselves, but this raid shows that we can get to them. Copyright applies to the internet too and we will continue to prioritize efforts to counteract these well-organized groups," said Anti-Piracy Agency lawyer Henrik Pontén in a statement.
The Sunnydale ring consists of 10 servers, together containing some 65 terabytes of pirated material ranging from movies and music to television series and computer games, the agency said.
Pontén said the server ring had collapsed as a direct result of the raid.
Speaking to newspaper Svenska Dagbladet, he also claimed that the Sunnydale ring was the source of all pirated material available on The Pirate Bay.
But this claim was disputed by The Pirate Bay's Peter Sunde.
"More than 800,000 people have uploaded to The Pirate Bay, so I don't believe it's the source of everything. But it is possible that it's a major source," he told Svenska Dagbladet.
One of the people suspected of responsibility for the server has admitted to some degree of involvement, according to the Anti-Piracy Agency, which said police were continuing with their investigations to trace the identities of those operating the server.