Rajab, who is also the president of the Bahrain Center for Human Rights, was arrested upon his return from Lebanon at the Bahrain International Airport in Manama on May 5.
He is accused of protesting without the ruling Al Khalifa regime’s permission and of insulting the authorities on social websites. Rajab has denied all the charges.
Rajab is a major critic of the regime and has played a significant role in anti-government demonstrations over the past few months.
Bahrainis have been holding peaceful anti-regime protests since February 2011.
The demonstrators hold King Hamad bin Isa Al Khalifa responsible for the death of protesters during the popular uprising.