| Valdemaras Martinkėnas | |
| Birth Date: | 1965 3, df=yes |
| Birth Place: | Krokialaukis, Lithuanian SSR, Soviet Union |
| Death Place: | Nova Gorica, Slovenia |
| Position: | Goalkeeper |
| Years1: | 1984–1987 |
| Years2: | 1987–1988 |
| Years3: | 1989–1991 |
| Years4: | 1991–1993 |
| Years5: | 1993–1994 |
| Years6: | 1994–1996 |
| Years7: | 1996 |
| Years8: | 1996–1997 |
| Years9: | 1997 |
| Years10: | 1997–1999 |
| Years11: | 2000 |
| Clubs1: | FK Žalgiris Vilnius |
| Clubs2: | FK Atlantas |
| Clubs3: | FK Žalgiris Vilnius |
| Clubs4: | Dynamo Kyiv |
| Clubs5: | Dynamo-2 Kyiv |
| Clubs6: | FC Wil |
| Clubs7: | FC Haka |
| Clubs8: | Lelle SK |
| Clubs9: | KAMAZ |
| Clubs10: | Kareda Šiauliai |
| Clubs11: | FC Kuressaare |
| Caps1: | 0 |
| Caps2: | 37 |
| Caps3: | 67 |
| Caps4: | 24 |
| Caps5: | 4 |
| Caps7: | 3 |
| Caps8: | 1 |
| Caps9: | 19 |
| Goals1: | 0 |
| Goals2: | 0 |
| Goals3: | 0 |
| Goals4: | 0 |
| Goals5: | 0 |
| Goals7: | 0 |
| Goals8: | 0 |
| Goals9: | 0 |
| Nationalyears1: | 1991–1997 |
| Nationalteam1: | Lithuania |
| Nationalcaps1: | 19 |
| Nationalgoals1: | 0 |
| Manageryears1: | 1999 |
| Manageryears2: | 2003–2004 |
| Manageryears3: | 2003–2004 |
| Managerclubs1: | Kareda Šiauliai |
| Managerclubs2: | FC Flora Tallinn (assistant) |
| Managerclubs3: | Estonia (assistant) |
Valdemaras Martinkėnas (10 March 1965 – 20 July 2004) was a Soviet and Lithuanian professional footballer and coach.
Born in Krokialaukis, Martinkėnas was the goalkeeper for the Lithuanian national team in the years after independence from the USSR, appearing in most of the qualifying games for the 1994 World Cup. He won 19 caps for his country.
He also won the Lithuanian league championship with Zalgiris Vilnius in 1991, and starred in Dynamo Kyiv's 1992–93 Ukrainian league championship win. Later, he became goalkeeping coach to the Estonian national side.
Martinkėnas died at the age of 39 in Nova Gorica in Slovenia, drowning in a strong current after having gone for a swim in a mountain river. He was the goalkeeping coach of Flora Tallinn at the time, and was in Slovenia preparing for their Champions League qualifier against NK Gorica.