The Stephen Lawrence Charitable Trust is in need of donations, which have declined in recent years, along with a reduction of support from public bodies.
The lack in funding could have a knock-on effect on the Stephen Lawrence Centre in Deptford, which is at risk of shutting down if donations do not increase.
Doreen Lawrence told the BBC: “We’ve been experiencing financial hardship for a while, but now as time’s gone on it’s got really bad. We need help desperately.”
The centre said they are not currently close to closing, but a significant lack of contributions will have a definite impact on its future.
“The events of recent weeks have highlighted that the cause of criminal justice has long been neglected.
“Now more than ever, a charity such as the trust… must not be allowed to fail for lack of funding.”
The Stephen Lawrence Centre was opened in 2008 in Deptford and maintains the trust’s aim of “promoting social justice by providing access and opportunities for all”.
The centre provides disadvantaged people with academic and vocational training.
His parents set up the trust after Stephen Lawrence was murdered in a racist attack at a bus stop in Eltham in 1993.
Gary Dobson, 36, and David Norris, 35, were convicted of his killing to 15 years two months and 14 years three months respectively on January 3.
A survey from the National Council for Voluntary Organisations published in December 2011 suggested charity leaders were not positive about their economic outlook for 2012.
60 per cent of respondents said their organisation’s financial situation had grown worse during 2011.