| Roles | Competed in Olympic Games |
|---|---|
| Sex | Male |
| Full name | Martsel Yosif•Koen |
| Used name | Martsel•Koen |
| Original name | Марцел Йосиф•Коен |
| Born | 5 July 1933 in Plovdiv, Plovdiv (BUL) |
| Measurements | 170 cm / 74 kg |
| NOC | Bulgaria |
| Games | Discipline (Sport) / Event | NOC / Team | Pos | Medal | As | |
|---|---|---|---|---|---|---|
| 1960 Summer Olympics | Shooting | BUL |
Martsel Koen | |||
| Small-Bore Rifle, Prone, 50 metres, Men (Olympic) | 8 | |||||
| 1964 Summer Olympics | Shooting | BUL |
Martsel Koen | |||
| Small-Bore Rifle, Three Positions, 50 metres, Men (Olympic) | 23 | |||||
| Small-Bore Rifle, Prone, 50 metres, Men (Olympic) | 25 | |||||
| 1968 Summer Olympics | Shooting | BUL |
Martsel Koen | |||
| Small-Bore Rifle, Three Positions, 50 metres, Open (Olympic) | 21 | |||||
| Small-Bore Rifle, Prone, 50 metres, Open (Olympic) | 24 |