The provincial government says it decided to raise the flag to show Saskatchewan's support for a free and democratic Ukraine.
Orest Gawdyda (GOW'-did-dah), president of the Ukrainian Canadian Congress branch in Regina, helped raise the flag.
He says the move sends a message to the people of Ukraine that Canadians support them.
Ferocious street battles between protesters and police in the Ukrainian capital, Kyiv, have left dozens dead and hundreds wounded in the last few days.
The violence strikes close to home for many residents in Saskatchewan, where about 13 per cent of the population has Ukrainian roots.
Gawdyda says he fears the worst is still to come.