An independent Uzbek information website, uznews.net, says the two were detained while crossing the Czech-German border on July 3.
Berlin granted both men refugee status after the violence that broke out in the eastern Uzbek city of Andijon in May 2005.
A German Foreign Ministry spokesman is quoted as saying the ministry has sent a request to the Czech government to release the detainees as soon as possible.
(Uznews.net, SNGnews.ru, RFE/RL's Uzbek Service)