The picket has been organized by the Ukrainian Congress in Latvia as part of the third international campaign Global Day Free Savchenko.
Participants of the protest held Latvian and Ukrainian national flags. A number of police officers monitored the peaceful picket.
Ukrainian Air Force pilot Nadiya Savchenko, 34, was captured by eastern Ukrainian separatists in June 2014 and then taken to Russia where she was falsely accused of illegally crossing the Russian border and killing two Russian journalists in Ukraine's southeastern region of Luhansk.
Her lawyer, however, has evidence that Savchenko had already been captured by the pro-Kremlin separatists when the journalists were killed, Mikola Pavluks, a representative of the Ukrainian Congress in Latvia, said earlier.
Savchenko may face a jail sentence of up to 25 years if the Russian court finds her guilty.
