Ukraine participated at the 2018 Summer Youth Olympics in Buenos Aires, Argentina from 6 October to 18 October 2018.
Mykhaylo Kokhan and Yaroslava Mahuchikh (both - athletics), Sofiya Lyskun (diving), Denys Kesil (swimming) represented Ukraine at the 2020 and 2024 Summer Olympics. Oleh Serbin (diving), Khrystyna Pohranychna (rhythmic gymnastics), and Ihor Troianovskyi (swimming) competed at the 2020 Summer Olympics. Oleh Doroshchuk (athletics), Nazar Chepurnyi (gymnastics), and Yaroslav Tkach (sport climbing) competed at the 2024 Summer Olympics. Yaroslava Mahuchikh won bronze at the 2020 Summer Olympics, becoming the first Ukrainian athlete from the 2018 Games to win a medal at both Youth and senior Olympics and the first Ukrainian to do that at the consecutive Games. In 2024, Mahuchikh became the first Ukrainian athlete who won gold medals at both Youth and senior Olympics. Mykhaylo Kokhan also won a medal at the 2024 Summer Games.
The following is the list of number of competitors participating at the Games per sport.
Ukraine qualified two archers based on its performance at the 2017 World Archery Youth Championships.
Ukraine qualified 13 athletes: 4 boys and 9 girls.
Ukraine qualified one player based on the Badminton Junior World Rankings.
Ukraine qualified a boys' and girls' team based on the U18 3x3 National Federation Ranking.
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Ukraine qualified two boats based on its performance at the 2018 World Qualification Event.
Ukraine qualified to compete in girls' combined team.
Ukraine qualified a mixed pair based on its performance at the 2018 Acrobatic Gymnastics World Championship.
Ukraine qualified two gymnasts based on its performance at the 2018 European Junior Championship.
Ukraine qualified one rhythmic gymnast based on its performance at the European qualification event.
Ukraine qualified one athlete based on its performance at one of the Karate Qualification Tournaments.
Ukraine qualified one boat based on its performance at the 2018 European Rowing Junior Championships.
Ukraine qualified one sport shooter based on its performance at the 2018 European Championships.
Ukraine qualified two athletes based on its performance at the 2017 World Youth Championships.
On 30 September 2017, Ukraine was handed a one-year ban from the IWF for doping violations which was in effect til mid-October. Therefore, Ukrainian athletes were unable to compete in Buenos Aires.
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