The march started at the Garden of Remembrance, which honors those who died in Irish rebellions from 1798 to the 1920s, The Irish Times reported. A masked woman riding a horse with a banner that said "No to Austerity" led protesters down O'Connell Street to the General Post Office, focus of the 1916 Easter Rising.
The demonstration featured a float with a giant skull labeled "ECB," or European Central Bank.
Michael O'Reilly, president of the Dublin Council of Trade Unions, addressed the crowd at the GPO.
"The evidence is clear -- you cannot cut your way out of a recession," he said. "On the contrary: with each cut in public spending, and with each euro taken out of the pockets of low and average earners in new or increased taxes, we are digging ourselves further into a hole."
Police estimated the crowd at 4,000. But the Times said protesters were still arriving in Dublin. Organizers said they expected about 10,000.