Naser Safarian and Mohsen Shahnazdar were freed Saturday, Iran's Fars news agency said, citing a statement by the Iranian Documentary Filmmakers Association (IDFA).
The fate of the four other filmmakers arrested at the same time, in mid-September, was not reported.
"Two documentary filmmakers detained recently for collaborating with a Farsi-language foreign network have been released," Fars said.
The ISNA news agency said Safarian was released on a bail of two billion rials ($160,000).
Iranian officials accused the six of "collaborating" with BBC Farsi – whose broadcasts are often scrambled in the Islamic republic – with the aim of "painting a black picture of Iran."
The BBC says the six were not staff or commissioned workers, but rather independent filmmakers whose films had appeared on its Farsi service.
Last week, the broadcaster alleged that Iranian authorities were harassing relatives of its London-based Iranian employees.
Iran bans any cooperation with foreign radio and television networks that broadcast in Farsi, including the BBC and the Voice of America.
A week after the filmmakers' arrests, Iran's Intelligence Minister Heydar Moslehi accused British spy agencies of launching "new destructive and anti-Iranian activities under cover of BBC Farsi."
Iranian officials have charged that the BBC fuelled the unrest that broke out following the disputed 2009 re-election of President Mahmoud Ahmadinejad.
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