| Medal record | ||
|---|---|---|
| Women's cross-country skiing | ||
Representing  Japan
| ||
| Asian Winter Games | ||
 |
1996 Harbin | 10 km freestyle |
|
1999 Gangwon | 5 km classical |
 |
1996 Harbin | 5 km classical |
|
1999 Gangwon | 10 km freestyle |
|
1999 Gangwon | 4 × 5 km relay |
| Junior World Championships | ||
|
1994 Breitenwang | 4 × 5 km relay |
Sumiko Yokoyama (横山 寿美子, Yokoyama Sumiko, born March 25, 1974) is a Japanese cross country skier who competed from 1993 to 2008. Her best World Cup finish was fifth in a 4 x 5 km relay in Switzerland in 2003.
Yokoyama also competed in four Winter Olympics, earning her best finish of tenth in the 4 x 5 km relay at Salt Lake City in 2002. Her best finish at the FIS Nordic World Ski Championships was 8th in the 4 x 5 km relay at Sapporo in 2007.