| Thomas Kläsener | |
| Height: | 1.87 m |
| Birth Date: | 1976 8, df=yes |
| Birth Place: | Gelsenkirchen, West Germany |
| Position: | Defender |
| Youthyears1: | 1984–1990 |
| Youthclubs1: | Resse 08 |
| Youthyears2: | 1990–1996 |
| Youthclubs2: | Erler SV |
| Years1: | 1996–2000 |
| Clubs1: | Schalke 04 II |
| Years2: | 2000–2001 |
| Clubs2: | SG Wattenscheid 09 |
| Caps2: | 15 |
| Goals2: | 1 |
| Years3: | 2001–2006 |
| Clubs3: | Schalke 04 II |
| Caps3: | 86 |
| Goals3: | 12 |
| Years4: | 2003–2006 |
| Clubs4: | Schalke 04 |
| Caps4: | 32 |
| Goals4: | 1 |
| Years5: | 2006–2007 |
| Clubs5: | Rot-Weiss Essen |
| Caps5: | 33 |
| Goals5: | 1 |
| Years6: | 2007–2008 |
| Clubs6: | SC Paderborn |
| Caps6: | 13 |
| Goals6: | 1 |
| Years7: | 2008–2009 |
| Clubs7: | FC Augsburg |
| Caps7: | 17 |
| Goals7: | 0 |
| Years8: | 2009–2011 |
| Clubs8: | RB Leipzig |
| Caps8: | 56 |
| Goals8: | 6 |
| Years9: | 2011–2013 |
| Clubs9: | SSV Markranstädt |
Thomas Kläsener (born 14 August 1976 in Gelsenkirchen) is a German former professional footballer who played as a defender.[1]