"The ruling of Moscow Region's Khimki city court should be left unchanged, the appeals are rejected," judge Musa Musayev announced.
Navalny's defence team will challenge the court ruling.
Navalny was detained on 17 January upon his return from Germany where he was treated for alleged poisoning. After the arrest, his supporters called for nationwide rallies that took place on Saturday.
Russian law enforcement bodies state that the opposition figure was arrested for violating probation terms for an earlier embezzlement conviction, and observed that the Saturday rallies were not authorised.