The Faslane base hosts four UK nuclear submarines armed with Trident intercontinental ballistic missiles.
"36 protesters have been arrested," the activist told Sputnik.
The demonstration began at 07:00 GMT and is set to continue until 15:00 as demonstrators attempt to keep the base shut. As many as 250 people took part in the protest.
"The protest is still on, gates of the base are still shut, the workers in the base who have been waiting in buses to get into the base have now all been sent home," the activist told Sputnik.
The renewal of the Trident program is a hotly contested topic being debated prior to next month's general elections in the United Kingdom. Scotland's pro-independence forces oppose the presence of nuclear weapons in the country.
The UK general election is scheduled for May 7, 2015.