The National Union of Workers (NUW) is joining the chorus of South Australians rallying today against the Rann Government.

Trade unions contest the SA Premier's recent tough budget designed to get state spending under control, which included replacing holiday leave loading for white collar public service staff with two extra days off and slashing 3700 jobs.

The budget cuts come as the Rann Government paid for a university intern to attend a trade fair in the Italian region of Puglia, placing increasing pressure on the SA Premier to justify his budget priorities.

NUW General Branch Secretary Sam Roberts said union officials and members would be out in force. "We're furious with the cuts," Mr Roberts said.

"Our members working in hospitals and TAFEs will be most affected, but these cuts will touch thousands of SA workers."

"Public sector wages and conditions are being slashed and existing rights to collective bargain are being ignored."

Mr Roberts said the union was concerned the needy would suffer most.

"The cuts to community support services and staff will decimate programs designed to help South Australia's most vulnerable people," Mr Roberts said.

"We encourage South Australians to turn out in force today and send a message to Mr Rann and Mr Foley that we will not tolerate this demolition of wages, conditions and services."

Australian Council of Trade Unions president Ged Kearney is scheduled to speak in Adelaide today.