She was the bronze medalist in the 2006 European U18 girls championship. She placed eleventh with 2.5/11. In the Superfinal she scored 4/9.
In the same year, Gunina competed for the first time in the Women"s World Championship: she defeated Gu Xiaobing in the first round, then she was knocked out by Alisa Galliamova in round two.
In January 2015, she took part in the Tata Steel Challengers tournament in Wijk aan Zee, the Netherlands, where she scored 5/13. At the Women"s World Chess Championship 2015 Gunina made it to the third round, where she was eliminated by Pia Cramling, after knocking out Camilla Baginskaite and Olga Girya.