Opponents of the award, who call themselves "Stuckists," stood outside the Tate Britain gallery on London's River Thames where the award is staged and called on Monday for the "tired" and "exhausted" show to be scrapped.
But curator Lizzie Carey-Thomas defended the institution, which dates back to 1984 and has been won by the likes of Gilbert & George, Richard Long, Anish Kapoor and Damien Hirst.
"Art has more of a place in contemporary British culture than ever before," she told Reuters at the Tate, where works by the four shortlisted artists go on display to the public from October 6-January 3, 2010.
"I think last year we had 90,000 visitors to the show which was the highest for a number of years. The YBAs (Young British Artists) helped to popularize contemporary art and bring it to a new audience, although the art has moved on since then."
The first rooms of the show are dedicated to Lucy Skaer, the only woman among the nominees.
Her works include tall, black, skittle-like sculptures made with coal dust and arranged in rows and in a pile on the floor.
"Leviathan Edge" (2009) is a partial skeleton of a male sperm whale visible through narrow slits in the wall.
"Lucy Skaer is slowing down the art of looking. You can't just grasp the art in once glance," said Carey-Thomas.
Scottish-based Richard Wright, who specializes in large wall paintings made for specific spaces, has adorned the far wall of a room with symmetrical, intricate gold-leaf patterns.
Italian-born Enrico David presents "Absuction Cardigan" (2009), a collage of sculptures, paintings and papier-mache "eggmen" described by the exhibition as a "parade of unruly characters" that represent the artist himself.
Finally, Richard Hiorns has covered half of a gallery floor with the black and grey metal dust of an atomized passenger aircraft engine, in a work designed to question our faith in technology and remind us of our own mortality.
Further works hanging on the walls contain cows' brains.
When the nominees, who must be British-based and aged under 50, were first unveiled, organizers said they were likely to be short on shock value and easier for the public to understand than previous versions.
The prize has earned a reputation for being deliberately provocative and out of touch with what people consider to be art, although the 2008 competition created little stir and 2009 may prove similarly uncontroversial.
Previous winners have included Grayson Perry, a cross-dressing potter, and Martin Creed, whose installation in 2001 featured lights going on and off in an empty room.
The winner of the prize, who picks up a cheque for 25,000 pounds, will be announced on December 7. Hiorns is the bookmakers' early favorite to triumph, while Wright is the 10/1 outsider.
Editing by Paul Casciato