The Russian scored a personal best 213.84 to beat the Olympic figure skating champion by over 15 points.
Russia's Sofia Samodurova stunned Olympic and defending champion Alina Zagitova in Minsk to take her first European title.
The 16-year-old was in tears after the skate of her life to score 213.84 and to distance her famous compatriot by over 15 points.
''I’m quite satisfied with the results of the European Championships and you must understand that it is quite hard to say something right now,'' Samodurova said after her victory.
''I’ve tried to keep myself in the right frame of mind for this performance and my skating impeccable. I haven’t understood yet that I’ve managed to get a gold medal. '' she said.
Finland's Viveca Lindfors clinched bronze a further four points behind Zagitova for the first international podium finish of her senior career.
Zagitova, who's also still 16, performed her free skate with several mistakes to end up with a disappointing 123.34. That was only good enough to finish fourth in the component.
''I don’t know exactly what has happened today, but I do hope that the best is yet to come for me,'' she said after the competition. ''Second place is still good because it could have been worse.''
She had claimed the 'small gold' medal in the short program earlier in the week, but the pressure appeared to get to her on Friday evening.
Skating to the Carmen Suite, the star fell on her triple Lutz, triple toeloop combination and put a hand down after her triple Lutz. She also under-rotated a triple flip in a later combination.
''Thank you to all my fans and the audience for their support because it helped me a lot with the performance and I’d like also to apologise for not doing my best performance today,'' the Russian said in a press conference with media.
Zagitova does not appear to have shrugged off her defeat to Rika Kihira at the ISU Grand Prix Final. Even in the short program she suffered a moment of drama.
She misjudged her landing on a triple flip and put her hand out for balance, withdrawing it just in time. She also under-rotated a triple loop.
Speaking to the media, including Olympic Channel, afterwards, she said: "I haven't been sleeping well lately before competition. I am satisfied although it could've been much better."
“I was just focused on having a clean skate,” said Zagitova, who was recovering from a disappointing fifth-place finish at last month’s Russian nationals. “I was deliberately trying not to show my emotions and I don’t plan to until the free skate. There were some flaws but they can be fixed. Now I need to get focused as much as possible for the free skate.”
Her miseries continued in the free skate. The PyeongChang gold medallist failed to break 200 points for the first time in her senior career.
Olympic silver medallist and two-time European champion Evgenia Medvedeva wasn’t competing in Minsk after failing to make the Russian team.
Samodurova made the most of her more experienced colleagues' absence and problems.
The Krasnoyarsk native has become European champion in her first senior season, after also qualifying for the Grand Prix Final in Vancouver.
She had finished two points behind Zagitova in the short program, scoring 72.88.
But unlike her fellow Russian, Samodurova was able to produce when it counted in the free skate.
Performing to burlesque music, she executed her opening triple flip, triple toeloop combination with precision.
She added a triple Lutz, triple loop, triple Salchow, triple flip, and two more double Axel combinations in her routine.
And it paid off.
Her scores in both the short and free programs, as well as her total, all broke her previous personal bests, set when she finished fifth in Canada.