| Katsuyuki Aihara | |
| Position: | Pitcher |
| Birth Date: | 24 July 1983 |
| Birth Place: | Saitama, Japan |
| Bats: | Right |
| Throws: | Right |
| Debutyear: | 2006 |
| Debutteam: | Chiba Lotte Marines |
| Statyear: | 2008 |
| Stat1label: | Win–loss |
| Stat1value: | 0–0 |
| Stat2label: | ERA |
| Stat2value: | 6.43 |
| Stat3label: | Strikeouts |
| Stat3value: | 2 |
| Teams: |
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is a professional Japanese Nippon Professional Baseball player. He is currently with the Chiba Lotte Marines.