The Romanian president's office on Sunday said all four are in the custody of Romanian authorities.
"They are unharmed and we will announce to the public when they will return to the country," said Adriana Saftoiu, a spokeswoman for President Traian Basescu.
The three Romanians - newspaper reporter Ovidiu Ohanesian, TV reporter Marie-Jeanne Ion and cameraman Sorin Miscoci - were kidnapped in Iraq on 28 March, along with their guide, Mohammed Monaf.
Their kidnappers had threatened to kill the hostages unless Romania pulls its 800 troops out of Iraq.
In a short videotape aired by Aljazeera, a masked spokesman for the Muadh bin Jabal Brigade said the three journalists had been freed "in response to requests from Saudi cleric Salman bin Fahd al-Odah and Muslims in Romania".
The video showed the spokesman reading from a prepared text standing over the four captives.
Aljazeera could not verify the authenticity of the videotape
An earlier video aired on Aljazeera had shown the journalists in handcuffs with pistols pointed at their heads.
Ion, a reporter for Prima TV, could be seen talking to the camera and clutching her hands as if pleading. In a separate audio message, they asked Romania's government to save their lives.
"I feel like a piece of me that was missing has now been restored. I never lost hope"
Father of released journalist Marie-Jeanne Ion
Miscoci, of Prima TV, said he would be the first killed if the Romanian troops were not withdrawn.
Basescu refused to withdraw the troops, saying the country would not negotiate its foreign policy with the kidnappers or pay them money to free them.
In recent weeks, Romanian authorities said they were in contact with the kidnappers and called on them not to kill the hostages.
Romanians held rallies and prayer vigils urging the release of the three journalists and the guide, who is married to a Romanian.
The Romanian Islamic and Cultural League sent five representatives on Saturday to Baghdad, and Islamic groups in Iraq also urged the captors to free the four.
Traian Basescu (L) refused to
withdraw troops from Iraq
"It's over. The nightmare has ended. We are waiting for them to come home now," said Petre Mihai Bacanu, managing director of the newspaper that employs Ohanesian, Romania Libera.
Ion's father, Vasile Ion, said Basescu informed him about his daughter's release. Vasile Ion, a senator with the opposition Social Democratic Party, had urged Parliament to take a stand on the captors' demands.
"I feel like a piece of me that was missing has now been restored," he told radio Europa FM. "I never lost hope."