The hijacking ended peacefully with his arrest, and police say he gave a voluntary statement admitting to the offence.
Most of the 55 passengers were quickly released, but some escaped just minutes before the six-hour standoff ended.
EgyptAir hijacker 'gave contradictory testimonies' on motive
Lawyer Eleni Loizidou attacked Seif al-Din Mohamed Mostafa's credibility, highlighting to a court that he had initially claimed that the hijacking was part of a bid to see his ex-wife and children in Cyprus after more than two decades.
Loizidou argued that the 59-year-old Mostafa never told Cypriot authorities that he was a member of an Egyptian anti-government group, as he is now claiming. She also said that Mostafa had not been subjected to persecution in Egypt for his political beliefs.
At present, Mostafa is sticking by an 18-page testimony in which he claims that he intended to expose Egypt's "fascist" government.
He is fighting extradition, claiming that he may be tortured or killed if returned from Cyprus to his country of origin.
Mostafa backtracked on an earlier statement given to police after his arrest, saying that it is "wrong" and that he only made the claims because he "trusted" them. Following this, he made the claim that he was part of an underground anti-government group.
Before the court, Loizidou highlighted the inconsistencies in Mustafa's testimony, including his claim that he is a pacifist despite also having admitted to volunteering for a suicide bombing mission in Lebanon in 1979.
Mostafa hijacked an Alexandria-to-Cairo flight on March 29 and forced it to land in Larnaca.