| Yūya Onaka | |
| Position: | Pitcher |
| Team: | Tokyo Yakult Swallows |
| Number: | 52 |
| Bats: | Left |
| Throws: | Right |
| Birth Date: | 31 January 1995 |
| Birth Place: | Kitakyushu, Fukuoka, Japan |
| Debutleague: | NPB |
| Debutdate: | May 9 |
| Debutyear: | 2017 |
| Debutteam: | Yokohama DeNA BayStars |
| Statyear: | 2020 season |
| Stat1label: | Win–loss record |
| Stat1value: | 1–2 |
| Stat2label: | Earned run average |
| Stat2value: | 5.71 |
| Stat3label: | Strikeouts |
| Stat3value: | 39 |
| Teams: |
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is a professional Japanese baseballpitcher for the Tokyo Yakult Swallows of Nippon Professional Baseball (NPB). He has previously played in NPB for the Yokohama DeNA BayStars and Hanshin Tigers.