Peter Krabowski, who will be taking part in the demonstration, told The Local: "It's an important opportunity to criticize the financial policies within the Eurozone, as symbolized by the ECB, and to make it public that there are alternatives to the current model."
The protesters and activists planning to rally in Frankfurt are part of the Blockupy alliance – a collection of various anti-capitalism and anti-austerity groups from across Europe.
To counter them, police are planning to deploy thousands of officers around the €1.3 billion building. The officers will be equiped with water cannons; helicopters and aircraft will be on stand-by should things get out of hand.
Authorities have also built barbed wire barricades around the ECB for extra security.
Spokespeople for the Blockupy protesters have accused the police and city authorities of "scaremongering". Frederic Wester said police were drawing up an "absurd civil war scenario."
"Such measures can act as a provocation. Particularly when the movement of protestors is restricted, that's when things can escalate," Krabowski told The Local.
Hannah Eberle for the Interventionistische Linke (Interventionist Left) vowed that demonstrators "will not allow the police to get in their way".
"We're fighting for a different, a democratic and social Europe," said Roland Suess of the anti-capitalist group Attac.
Blockupy outlines its main goal as to create a European movement that overcomes the policy of austerity in order to start building democracy and solidarity from the bottom up.
The alliance also declares itself to be strongly against any racist or nationalist splinter groups, as well as conspiracy theories and anti-Semitism.
The movement's origins can be found in New York's anti-capitalist 'Occupy Wall Street' demonstrations, which then spread to Germany in late 2011 as 'Occupy Frankfurt'.
The protest is particularly timely because of the growing German-Greek tensions over the recent bailout extension. The Greek debt crisis has become a central issue for the anti-austerity demonstrators.