Julia Samoilova was banned from entering Ukraine for three years because of her “illegal” visit , the Ukrainian SBU security service said.
Samoilova, 27, has confirmed that she sang in Crimea in 2015. Ukraine is due to host Eurovision in Kiev, in May.
A Russian foreign ministry source described the decision as “cynical and inhumane”.
A senior Russian politician, Frants Klintsevich, was quoted by Ria-Novosti news agency as saying Russia would boycott future Eurovision contests if the organisers failed to stand up for the singer.
The SBU has blacklisted at least 140 other Russian artists.
Russia and Ukraine have been at loggerheads since the annexation of Crimea and subsequent fighting in east Ukraine, which Moscow is accused of stoking.
Ukraine is hosting the competition after its singer, Jamala, caused an upset by winning in Sweden last year.
Her song, 1944, was about Joseph Stalin’s mass deportation of the Crimean Tatars during World War Two.
The SBU (Security Service of Ukraine) said earlier it would verify information about Samoilova’s visit to Crimea and take a decision.
Last month, the contest was rocked by the resignation of 21 top-level staff who organise the event.
The Ukrainian Eurovision team said they had been stripped of major responsibilities in December, when a new boss was appointed to the organising committee.
According to their resignation letter, they were “completely blocked” from making decisions about the show.
The EBU, which founded Eurovision, told Ukraine’s public broadcaster to “stick to the timeline” despite the upheaval. It insisted the event would go ahead as planned in Kiev.
Join GhanaStar.com to receive daily email alerts of breaking news in Ghana. GhanaStar.com is your source for all Ghana News. Get the latest Ghana news, breaking news, sports, politics, entertainment and more about Ghana, Africa and beyond.