Mansour's lawyers, who told Al Jazeera of the German decision, were expected to meet him
following his release on Monday.
Earlier reports had said a court in Germany was about to consider Egypt's request to extradite Mansour, one of the Arab world's most respected journalists.
Al Jazeera's Paul Brennan, reporting from Berlin earlier, said a temporary detention investigative judge concluded his investigation with Mansour on Sunday, after which he was transferred to Moabit prison in Berlin.
Our correspondent said that the court and Mansour's lawyers are "making the arrangements for his departure."
Saad Djebbar, one of Mansour's lawyer, said that while his client was "very happy" about the court's decision, he was also "very said" that the Al Jazeera journalist was detained in the first place.
Another lawyer Patrick Teubner said that with the court decision, Mansour could now leave Germany.
Dozens of supporters of Mansour had protested in front of the Berlin court building where he was held.
Fazli Altin, another lawyer of Mansour said that Germany was getting involved in a "politically tainted case".
Responding to questions on Mansour's arrest, a German foreign ministry spokesman told Reuters news agency earlier that no one would be extradited from Germany if the defendant risked facing the death penalty.
More than 25,000 people had signed a petition calling on German Chancellor Angela Merkel to release Mansour.
For its part, the Committee to Protect Journalists (CPJ) called on Egypt to stop pursuing Al Jazeera journalists.
Source: Al Jazeera