Protesters have gathered at the Waihopai spy base near Blenheim, demanding the closure of the Government operated satellite station.
It is the first time a protest has been held at the site since 2008, after three men were charged with damaging a dome covering a satellite dish at the base.
Green Party MP Keith Locke says there are about 50 people gathered outside the base to show solidarity with the men by popping white balloons.
He says the base is merely a front for American intelligence gathering, and hopes Saturday's protest will persuade the Government to engage in public debate about he calls its true purpose.
