The Russian youngster held off the challenge of reigning champion Alina Zagitova to deny her compatriot the chance of clinching back-to-back European titles.
The Krasnoyarsk-born skater sat second in the standings after the short programme, but Samodurova dazzled in the free skate competition to cash in a score of 140.96.
A total score of 213.84 proved enough to take the title as Olympic champion Zagitova's free skate routine could only clinch fourth spot to finish eight points behind the overall winner.
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Finland's Viveca Lindfors completed the podium line-up with a total score of 194.40 to earn a first European Championship medal.
Elsewhere, defending European ice dancing champions Guillaume Cizeron and Gabriella Papadakis are on course to seal a fifth consecutive title after a blistering start in Minsk.
The French pair breezed to the top at the halfway stage with a total segment score of 84.79 to build a lead over Russian rivals Alexandra Stepanova and Ivan Bukin.
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The Russian 2018 European bronze medallists recorded a rhythm dance score of 81.37 to keep their gold medal winning ambitions alive, while Italians Charlene Guignard and Marco Fabbri sit in third.
Victory in the competition would see Cizeron and Papadakis overtake Jayne Torvill and Christopher Dean in the all-time European championship medal ranks and the French pair are confident ahead of Saturday's free dance finals.
"It all went really well. We are proud indeed of what we have done," said Papadakis. "Technique wise it was on point as well."
Cizeron added: "We were really concentrated on all the technical elements that we've been working on. Indeed it's only the second competition of our season.
"For me it didn't feel like it was the best performance that we could show, but it's interesting to know that even if we're not at 100% we can still deliver."
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