Friday's peaceful demonstration in the capital, Amman, drew nearly 2,000 people, including youth activists and Muslim Brotherhood members, united in the election boycott and in demands that King Abdullah II cede some of his powers.
The Muslim Brotherhood, Jordan's largest opposition group, has renewed calls for King Abdullah to transfer his authority to appoint governments to the "people", meaning an elected parliament.
More than 1,500 candidates, including 213 women, have been registered for the January 23 election for 150 seats in the lower house of parliament, which the opposition groups have boycotted over a lack of reform.
"We reject cosmetic elections and schemes against our demands for reform," read a banner at the rally, organised by the Islamic Action Front, the political arm of the Muslim Brotherhood.
The protesters chanted: "The people want to reform the regime," and "listen Abdullah, the people demand freedom."
"The rule of the people is coming. Demonstrate and demand reform. The people will continue to demand regime reforms until the regime realises that there is no room for procrastination," Hammam Said, leader of the Muslim Brotherhood, told the demonstrators.
He also gave a sermon condemning the elections, saying they were merely giving the impression of democracy.
"The elections that are taking place in the next few days, are only taking place so that others may say: democracy does exist in Jordan," Said said.
The Brotherhood has said it will boycott the election in protest at constituency boundaries it says are unfair, and at the failure to move towards a constitutional monarchy with an elected prime minister, rather than one named by the king.
Meanwhile, hundreds of activists held anti-government protests in the southern cities of Karak and Maan, urging citizens to boycott the polls.
The demonstration comes just five days before elections that will for the first time see a prime minister emerge from among the winning candidates, rather than by appointment by the king.
The elections will be Jordan's first since the Arab Spring uprisings started in late 2010.
Activists claim the polls are already marred by voter fraud and "vote buying", with candidates allegedly offering as much as 1,200 dollars for a single vote.
The authorities have pledged to crack down on the practice.
The independent electoral commission referred two candidates and 15 citizens to the courts earlier in the month for suspected voting fraud.
Pro-democracy activists have called for constitutional reform that would transfer the monarch's authority, to appoint and dismiss governments, to parliament.
Some 2.2 million of 3 million eligible voters have registered for the polls. Additionally there are 15 quota seats reserved for women, and 27 seats reserved for the national electoral lists.
Ruling out any changes to the constitution, the king announced on Wednesday that the incoming parliament will form the next government.