He's dressed in a stained flannelette shirt, shorts and shoes with holes in them.

But despite the cold wind that whips through his position on the walkway in Brisbane's CBD, Dougie Gillespie, who has lived on the streets of Brisbane for 15 years, doesn't want people's sympathy. He just wants to see them smile.

In front of him, he's propped two handwritten cardboard signs. The first reads:"The Silent Busker." The second: "Very Tiring"

"What gives me my kicks, you know, is making people have a chuckle, have a laugh," he says. "There are people in wheelchairs, or with serious health problems, you know. And the men in suits they're always rushin' around, rushing here, rushing there and then they see me and me' sign and it makes them laugh during their day. That's good stuff, you know."

But while humour might get him through the day, at night the picture for Dougie, and many other homeless people like him, is grim.

With night time temperatures plummetting in South-east Queensland, the city's homeless shelters are having to turn people away as more and more homeless seek warm beds for the night to escape the winter chill.

One of the city's main emergency housing shelters, Pindari Women's Shelter at Spring Hill has been forced to turn away 90 women a month because it does not have enough beds.

There are only about 50 emergency beds for women in the city, 200 for men and 30 for young people.

Charity organisations across the city estimate there are more than 4000 homeless people in Brisbane, with about 400 squatting in the CBD alone.

"In the past three months, 3000 homeless have come through our doors," Queensland Council of Social Service president Karyn Walsh said.

Charity groups expect the problem only to get worse, as rising costs of living force more and more people beneath the poverty line.

The Saint Vincent de Paul Society has reported an unprecedented spike in calls for help prompted by cold weather and rising living costs.