A NSW youth homelessness peak body is urging the state government to provide adequate COVID-19 relief funding to support a sector already stretched.

Cramped emergency housing, a lack of supplies and staff shortfalls could severely limit the ability of charities to help young people living on the streets during the COVID-19 crisis.

The peak body for organisations that help the state's homeless youth says governments must ensure vulnerable people have access to shelter, food and medical supplies during the pandemic.

Yfoundations chief executive Pam Barker argues the industry was already stretched before the crisis with more than 9000 young people experiencing homelessness every night in NSW.

She says there was no funding for the sector in this week's $2.3 billion state stimulus package.

"Our system is focused on picking up the pieces after the damage has already been done but we are calling for more immediate funding to prevent this crisis from damaging our most vulnerable," Ms Barker said in a statement on Wednesday.

She told AAP the sector was suffering as the workforce slims down due to coronavirus fears. It's a requirement that all shelters have 24/7 supervision for young people under 18.

Demand for services will increase if schools close down.

"It's imperative for specialist homelessness services to stay open with adequate staffing in order to keep young people safe and off the streets," Ms Barker said on Wednesday.

Social distancing measures mean more young people are seeking shelter as they are no longer able to stay in temporary accommodation - such as on a friend's couch.

But at the same time, fewer beds are available in refuges, as they work to adhere to new hygiene guidelines.

At many shelters young people are responsible for buying their own food to help teach them vital life skills - rather than the shelters providing food from bulk suppliers.

Ms Baker said a lack of supplies was a major cause of stress for vulnerable young people, many of whom also fear losing their casual employment.

She's calling on supermarkets to support vulnerable young people who are struggling to access vital supplies as has been done for the elderly and people with disabilities.

The Victorian government has provided $6 million to their social services sector as part of its COVID-19 relief package and Ms Barker says that needs to be matched in NSW.