The Muslim Brotherhood's political organization, Islamic Action Front, said the "Friday to Rescue the Nation" rally and march was intended to protest economic hardship and demand a less centralized government, with more opposition seats in Parliament.
Protesters, including some from Islamist movements and leftist parties, demanded the right for voters to elect the prime minister, who is now appointed by the king, ANSAmed -- the Mediterranean hub of Italy's ANSA news agency -- reported.
An estimated 2,000 security personnel watched as members of more than 80 political groups gathered in the Jordanian capital following noon prayers, The Jordan Times reported.
"We have had four governments, national dialogues, endless committees and we still haven't seen any real change on the ground," said Mohammed Omar of Irbid at the rally. "We are all one people, and we all want reform."
The event included a march to downtown's Palm Square, the site of previous protests, some of which turned violent. Citing police sources, ANSAmed reported some protesters carrying weapons and sticks were arrested before they reached the protest area.
The demonstration ended without incident and organizers said it would be the first of several mass protests intended to push for reform.
The pro-monarchy Youth Coalition of Loyalty and Allegiance canceled a planned counterdemonstration, with organizers saying they wanted to avoid a confrontation, CNN reported.
Abdullah, who became Jordan's king in 1999 after the death of his father, Hussein, has faced waves of unrest since January 2011.
Government spokesman Samih al-Maitah said the king's decision to dissolve Parliament and call early elections was part of his promised reforms.
"This was not a surprise decision," al-Maitah said.
Parliamentary elections will be held by early next year and be overseen by an independent commission, he said. The Parliament was elected almost two years ago.
Eighty-nine members of the 120-seat Parliament signed a motion of no-confidence against the government of Prime Minister Fayez Tarawneh Sept. 2 over rising fuel prices and "because of recent appointments in top posts based on nepotism," the official Petra news agency reported.
IAF Deputy General Secretary Nimer Assaf told CNN the Parliament dissolution had been "expected." But "as far as we are concerned, this is not the right step forward," he said.
There should be democratic election law reform and "real" changes to Jordan's constitution, he said.
Parliament should have the right to dissolve itself, and the prime minister should be elected by the public, he said.
Abdullah promised in June 2011 the government would in the future be elected, not appointed. But his statement then did not specify any timetable for the change.