Ahmed Maher, a founder of the April 6 movement that used social media to kindle the uprising that toppled Hosni Mubarak in 2011, is the latest in a series of activists detained by Egypt's new Islamist rulers.
He was returning to Egypt, via Austria, after speaking as a panelist at a conference on May 6 by the New America Foundation, entitled "Egypt in Transition".
"Airport security arrested him and said he was wanted by the General Prosecution on accusations of inciting demonstrations in front of the Interior Minister's home," a security source said, adding that the case will be transferred to the prosecution for investigation.
Hundreds of members of the April 6 movement staged a demonstration in front of the Interior Minister's home in March demanding the release of activists who were arrested in a security crackdown.
Four of the movement's members were arrested after the demonstration, said Amal Sharaf, the movement's spokesperson.
"I think they are punishing us and trying to stop us from what we are doing but of course they will not succeed because we will continue," she said.
Egypt, which has undergone more than two years of political instability, faces regular protests by opponents of the Islamist leader Mohamed Mursi who came to power in June.
Another prominent activist, Ahmed Douma, was detained late last month over accusations of insulting the president in a case that activists said highlighted a crackdown on dissent by the Islamist government.
Douma was one of five activists served with arrest orders in March based on accusations that included inciting aggression during street clashes near the Muslim Brotherhood headquarters.
The United States, which supplies $1.3 billion in military aid to Egypt each year, expressed concern in March over reports that arrest warrants had been issued for political activists.
Dozens of cases of "insulting the president" have been brought since Mursi took office. Activists say the government is using the courts to target its liberal and secular opponents.
Last month Egyptian prosecutors summoned a television satirist over allegations of insulting the president and Islam.
Bassem Youssef, whose programme has been compared to The Daily Show of U.S. satirist Jon Stewart, was released on bail of 15,000 Egyptian pounds after he turned himself in.