The director of Cage has been charged under the Terrorism Act, the campaign group said.
Muhammad Rabbani faces a charge of failing to disclose his password after being detained at Heathrow Airport under counter-terrorism stop-and-search powers.
A tweet from the group on Wednesday read: “Our Director Muhammad Rabbani has been charged for failing to disclose his password under Schedule 7 of the Terrorism Act.”
Cage describes itself as an “independent advocacy organisation working to empower communities impacted by the War on Terror”.
A spokesman for Cage said Rabbani was charged with wilfully obstructing or seeking to frustrate a search examination under Schedule 7 over the incident at the airport in November.
He said he will be challenging the charge and is due to appear at Westminster Magistrates' Court on June 20.
The Metropolitan Police confirmed that Rabbani, 36, attended an east London police station on Wednesday.
The charge said that "on 20 November 2016, at Heathrow Airport, he did wilfully obstruct, or sought to frustrate, an examination or search under Schedule 7 of the Terrorism Act 2000, contrary to paragraph 18(1)(c) of that Schedule".