| Toyoji Aihara | |
| Nationality: | Japanese |
| Sport: | Sprinting |
| Event: | 400 metres |
| Birth Date: | 7 January 1914 |
was a Japanese sprinter at the 1936 Summer Olympics.
Aihara competed at the Olympics at the same time he was attending Chuo University in Tokyo. He joined the postal service after graduating.[1]
Aihara competed in the men's 400 metres and the men's 4 x 400 metres relay events at the 1936 Summer Olympics.[2] He competed in the Hakone Ekiden relay race in 1937 and won the 400 metre and the 400 metre hurdles events at the 1937 Japan Athletics Championships.