At least 200,000 people marched though the centre of Amman in the largest show of public anger over the November 9 bombings, police and organisers said.
Many protestors chanted: "Zarqawi, from Amman, we say to you: you are a coward."
The Jordanian-born Zarqawi defended the bombings in a voice recording posted on the internet, which has not yet been verified.
The voice on the audiotape insisted it had not been al-Qaeda's intention to target the wedding party which was hit in the triple suicide bombings that killed 59 people, saying the group had information the hotels were being used by US intelligence agents.
"If we'd wanted to carry out bombings in the middle of a wedding, there are wedding halls all over the country and their doors are open," said the voice.
"God knows that the decision to target these hotels was taken only after ascertaining that they had become bases for Jewish and America security services," the voice added.
"If we had wanted to kill innocents as the apostate (Jordanian) regime claims, we would not have resorted to sacrificing the lives of those who got through the security barriers," the voice said.
In the aftermath of the attacks, even bloggers on extremist Islamist internet forums criticised Zarqawi for the strikes, with some calling on him to explain the purpose of attacks that killed mostly Jordanians.
The audiotape also warned Jordanians to stay away from luxury hotels like the three hit in this month's bombings, as well as the diplomatic missions of countries which took part in the 2003 invasion of Iraq.
To end al-Qaeda attacks in Jordan, the tape demanded the departure of British and US troops from the kingdom, the closure of the US and Israeli embassies and an end to training in Jordan for Iraq's fledgling security forces.