Erkin Aknazarov received a four-and-a-half-year sentence, while Joldoshbek Abdiev was sentenced to four years in jail.
The two were arrested when police broke up the rally in front of the Government House in Bishkek.
Lawyers for Aknazarov and Abdiev told RFE/RL's Kyrgyz service they will appeal to a higher court in Bishkek. They say the charges are politically motivated.
Kyrgyz authorities have also initiated criminal proceedings against some opposition leaders on charges of organizing public disorder.
The opposition supporters say the police provoked violence at what had been a peaceful rally by firing tear gas at the gathering. They admit that rally participants threw stones toward police-- but only after police had fired tear gas.
RFE/RL Central Asia Report
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