Julia Samoilova is set to represent her country in Kiev in May with the song Flame is Burning.
However, her admission she performed in Crimea since it was annexed by Russia in 2014 may compromise her attendance.
Ukraine's SBU security service has blacklisted 140 Russian artists, although she is not on the list so far.
Samoilova, 27, has confirmed that she sang in Crimea in 2015.
Russia and Ukraine have been locked in political conflict since the annexation of the region three years ago.
An SBU spokeswoman, Olena Gitlyanska, wrote on Facebook it would now "study the question and take a balanced decision on her entry into Ukraine".
Kremlin spokesman Dmitry Peskov, speaking to Russian news agency TASS, denied that Samoilova's selection was a provocation by Russia.
He said: "Undoubtedly, we would like to avoid politicising the Eurovision contest.
"We believe it absolutely unacceptable as far as the development of this international contest is concerned."
Russia announced Samoilova as its 2017 entry on state TV on Sunday, just one day before the nomination deadline.
Russian MPs and musical artists had been among those urging a boycott of Eurovision over its perceived politicisation.
Ultra-conservative lawmaker Vitaly Milonov said that Russians would be "unwelcome guests in a country seized by fanatics".
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.
In addition to the Crimea flashpoint, Ukraine accuses Moscow of arming separatist rebels in its eastern Donbas region, in a conflict that has claimed 10,000 lives since 2014.
Samoilova is due to perform in the second semi-final of the Eurovision Song Contest on 11 May in Kiev.
If she wins through she will take part in the final two days later.
Russia has announced it will now take part in Eurovision 2017 in Ukraine, appearing to end speculation of a boycott for political reasons.