| Willi Koslowski | |
| Birth Date: | 17 February 1937[1] |
| Birth Place: | Gelsenkirchen, Gau Westphalia-North, Germany |
| Position: | Forward |
| Youthclubs1: | Buer 07 |
| Youthclubs2: | Schalke 04 |
| Years1: | 1957–1963 |
| Clubs1: | Schalke 04 OL West |
| Years2: | 1963–1965 |
| Clubs2: | Schalke 04 Bundesliga |
| Caps2: | 39 |
| Goals2: | 12 |
| Years3: | 1965–1967 |
| Clubs3: | Rot-Weiss Essen |
| Caps3: | 25 |
| Goals3: | 2 |
| Nationalyears1: | 1962 |
| Nationalteam1: | West Germany |
| Nationalcaps1: | 3 |
| Nationalgoals1: | 1 |
Willi Koslowski (17 February 1937 – 11 July 2024) was a German professional footballer who played as a forward. He scored his only goal in his games for West Germany on the day of his debut, the third one of the West Germans in a 3–0 win over Uruguay in April 1962. He added two further appearances, one at the 1962 FIFA World Cup against Switzerland (2–1) at Estadio Nacional de Chile on 3 June, the same year.[2] Koslowski died on 11 July 2024, at the age of 87.[3]