Joe Corre, the son of Sex Pistols manager Malcolm McLaren and fashion designer Dame Vivienne Westwood, burnt the items on the 40th anniversary of the Sex Pistols debut single.
The 48-year-old told the crowd that "punk was never meant to be nostalgic".
The protest was aimed at official plans to celebrate the movement's 40th anniversary.
Mr Corre said his collection of clothes, posters and other music-related items was worth £5m.
