The temporary exhibition, called "Franco, Victory, Republic, Impunity and Urban Space", features sculptures placed on Barcelona's streets more than 40 years after the death of the dictator, which began the country's transition to democracy.
One sculpture depicts a headless Franco on horseback, another pays homage to the victory of his troops in the Spanish civil war. Both attracted anger and eggs within minutes of going on display, according to an AFP photographer.
A Franco's victims' group held a silent protest during the presentation of the works, while Catalan separatists chanted "no fascists on our streets".
People hold up the names of Franco victims. Photo: AFP
But Barcelona deputy mayor Gerardo Pisarello said the aim of the exhibition was "to denounce the crimes of Francoism and impunity, even in democracy".
Protestors clash at the door to the exhibition. Photo: AFP
Catalan nationalists argue that the exhibition, scheduled to end in January, trivialises the crimes of Franco's dictatorship, which came down hard on regional separatists.
During its transition to democracy, Spain passed a law granting amnesty for crimes committed by the dictatorship during the 1936-39 Spanish civil war.
The 1977 amnesty law prevents Spain from investigating and trying the crimes of the civil war era and the repressive right-wing dictatorship of General Franco that followed until his death in 1975.
Despite another law requiring the removal of Francoist symbols from public places, some are still present in many municipalities.