An Egyptian security official told AFP on Wednesday that police raided the offices of Al-Alam satellite channel on Monday and confiscated equipment including cameras because it did not have a licence to operate in Egypt.
However, the channel's website said it was raided because of its alleged involvement in a film which says that Sadat was killed for signing the 1978 Camp David Accords that led to a 1979 peace treaty with Israel, the first by an Arab country.
Al-Alam rejects "the Egyptian government's unfounded accusation of the news network's involvement in producing an Iranian documentary dubbed 'Assassination of a Pharaoh'," the website said.
Al-Alam's Cairo bureau chief Ahmed al-Soyufi was quoted as saying that the channel had no link with the documentary's producers.
Egyptian Foreign Minister Ahmed Abul Gheit earlier this month condemned the film, days after Egypt summoned Tehran's envoy in Cairo to lodge a formal protest over the airing of the film.
Diplomatic ties between Egypt and Iran were severed in 1980, a year after the Islamic revolution, in protest at Egypt's recognition of Israel, its hosting of the deposed shah and its support for Iraq during its 1980-1988 war with Iran.
Relations have recently warmed, with both countries signalling a willingness to restore ties.