His comments came as Cuba began celebrations to mark the 50th anniversary of its revolution.
The veteran leader said on Saturday his country would not accept assistance from those "historically responsible for slave trafficking, looting and even the extermination of entire peoples".
"The Cuban government, out of a basic feeling of dignity, rejects any humanitarian aid, or remaining aid, that may be offered by the governments of the European Union," said Castro addressing a crowd in the city of Santiago.
"Our country will only accept aid … from local and regional groups, non-governmental organisations and solidarity movements, which don't impose any political conditions on Cuba," he said.
Castro's remarks came as an apparent reaction to an EU declaration in Brussels last Monday that respect for human rights on the communist-ruled Caribbean island had "severely deteriorated."
Last year's EU budget foresaw 15 to 20 million euros (US $17 to US$22.7) in aid for Cuba, of which 400,000 euros has been delivered.
Cuba has come under increasing international criticism in recent months after it sentenced 75 dissidents to stiff jail terms in April. A month later, it executed three people for trying to hijack a ferry to the US.
In an apparent response to the April crackdown, the EU froze Havana's application to join the aid accord known as the Cotonou Agreement. It also started inviting Cuban dissidents to its national day embassy receptions in June, which Cuban officials stopped attending.
Castro led huge marches to the Cuban embassies of Spain and Italy and attacked Spanish Prime Minister Jose Maria Aznar and Italian Premier Silvio Berlusconi, reportedly likening Aznar to Adolf Hitler and calling Berlusconi a "fascist."
'Cuba does not need the help of the European Union to survive'
President Fidel Castro
A US human rights group on Saturday said renowned Cuban dissident Marta Beatriz Roque was in critical condition in jail and should be released.
"These innocent intellectuals are dying in Cuban dirt cells simply for opposing Fidel Castro," said a statement from the group, Judicial Watch.
Cubans are remembering events in 1953, when the 26-year-old Castro led about 120 fighters in an attack on some 800 troops at the Moncada garrison in Santiago de Cuba.
The rebels were defeated and Castro was arrested, but Cubans still commemorate the date as the start of the revolution.
The celebrations include firework displays, cultural events and an appearance by Elian Gonzalez - the child at the centre of a highly publicised custody dispute between the US and Cuba in 2000.
Addressing a reportedly 10,000-strong audience at the Moncada barracks, Castro accused the EU and the US of working together to crush the Caribbean state.
"Cuba does not need the help of the European Union to survive," he said.
The EU is Cuba's largest trading and investment partner. European visitors provide the bulk of the island's tourism, Cuba’s primary source of hard currency.