| Ryoji Katsuki | |
| Position: | Pitcher |
| Birth Date: | 22 January 1984 |
| Bats: | Right |
| Throws: | Right |
| Debutleague: | NPB |
| Debutdate: | April 29 |
| Debutyear: | 2010 |
| Debutteam: | Chiba Lotte Marines |
| Statyear: | 2016 |
| Statleague: | NPB |
| Stat1label: | Win–loss record |
| Stat1value: | 4-3 |
| Stat2label: | ERA |
| Stat2value: | 4.58 |
| Stat3label: | Strikeouts |
| Stat3value: | 55 |
| Teams: |
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Ryoji Katsuki (香月 良仁, born January 22, 1984, in Kurume, Fukuoka) is a Japanese former professional baseball pitcher in Japan's Nippon Professional Baseball. He played with the Chiba Lotte Marines in 2010 and from 2012 to 2016.
His elder brother Ryota is also a former professional baseball player.