"The people want to reform the regime. Freedom, freedom, down with Abdullah. God is greater than injustice Abdullah your era is gone," chanted crowds, which AFP estimated at more than 10,000 people, including Islamists and leftists.
"The people want the fall of the regime. Abdullah, reform or leave, you have lost legitimacy," they shouted angrily outside the Husseini Mosque in downtown Amman.
Publicly insulting the king or calling for his ouster is rare in Jordan because it is illegal and can result in jail.
Demonstrators held banners reading, "Playing with prices means playing with fire," "This is a real revolt against corruption" and "No reform without political and economic change. Long live the revolt of Jordanians."
Police prevented them from heading for the palace around eight kilometres (five miles) from the mosque, but no clashes were reported, an AFP reporter said.
Zaki Bani Rsheid, deputy leader of the opposition Muslim Brotherhood, told AFP: "Those who are calling for the fall of the regime are increasing because of wrong polices that reject people's demands."
"This cannot and should not be ignored. The regime must reform before it is too late."
The protesters said they plan another demonstration at around 7:00 pm (1600 GMT) near the interior ministry.
Near Amman in Baqaa, the country's largest Palestinian refugee camp, around 2,000 people protested against price rises.
"Police had to fire tear gas after some 200 demonstrators hurled stones at police and tried to block a main road in the camp," a security official told AFP.
Similar but smaller demonstrations took place elsewhere, including in the southern cities of Tafileh, Karak and Maan, as well as Irbid and Jerash in the north.
The unrest erupted late on Tuesday after the announcement of a 53 percent increase in the price of household gas and a 12 percent rise in petrol.
Prime Minister Abdullah Nsur said the increases are necessary to help reduce a projected budget deficit of 3.5 billion dinars (around $5 billion dollars/3.9 billion euros) this year.
Riots left one person dead and 71 injured, mainly policemen, according to police who arrested 158 people and recorded around 100 incidents of rioting, vandalism and theft nationwide.
A police statement said that 30 people were released from detention on Friday.
The Muslim Brotherhood has demanded that the king cancel the price hikes and postpone January 23 general elections, which the group said it will boycott.
Despite the unrest, US State Department deputy spokesman Mark Toner said on Thursday Jordan remained an "important strategic partner."
However, the US embassy has warned Americans to avoid areas where demonstrations are being held, while saying it was "carefully monitoring the security situation."
Saudi Arabia also urged its citizens to stay away from public gatherings and universities in Jordan, state news agency SPA reported.
Copyright AFP (Agence France-Presse), 2012