Zuzana Hejnová (Czech pronunciation: [ˈzuzana ˈɦɛjnovaː]; born 19 December 1986) is a Czech athlete. She competes in the 100 metres, the 100 metres hurdles, the 400 metres and the 400 metres hurdles, and also the heptathlon. She is the current World Champion in the 400 metres hurdles. Her sister, Michaela, is also an Olympic athlete.
In 2003, Hejnová competed at the 2003 World Youth Championships in Athletics at Sherbrooke, Canada and won the gold medal in the 400 metre hurdles with a time of 57.54. A year later, she returned at Grosseto, Italy at the 2004 World Junior Championships. This time she won the silver with a time of 57.44 in the 400 m hurdles, defeated by the Russian, Ekaterina Kostetskaya, who won gold by a large margin at 55.55 seconds.
Her current personal bests are 14.11 in the 100m achieved at Ostrava on 3 September 2005; 13.77 in the 100 metres hurdles at Stará Boleslav on 13 June 2003; 53.04 in the 400 m at Kladno on 28 June 2008; and 54.90 in the 400 m hurdles recorded at Monaco on 28 July 2009.
In early March 2008 Hejnová competed in the 400 metres at the 2008 IAAF World Indoor Championships and reached the semi finals but did not qualify to reach the final. She did however, reach the final with the Czech relay team in the 4 × 400 metres relay in a team which included her, Zuzana Bergrová, Denisa Ščerbová, and Jitka Bartoničková. They finished 4th, with a time of 3:34.53, but were over 5 seconds slower than the Americans who took bronze with a time of 3:29.30.
On 21 June 2008, she competed for the Czech Republic at the 2008 European Cup in Athletics.
Hejnová competed in the 400 metres hurdles at the 2008 Beijing Olympics. She qualified for the second round with the thirteenth fastest overall time of 55.91 seconds and for the final with 55.17. In the final she finished seventh with 54.97, only one hundredth behind her personal best at the time.
She won the 400 metres hurdles at the European Team Championships with a new national record of 53.87 seconds. On 8 July 2011 she improved her national record to 53.29 seconds.
Hejnová won the first round of the Women's 400 m Hurdles at the 2012 Summer Olympics. On 8 August 2012 Hejnová won the bronze medal in the finals.
Hejnová won Diamond League races over 400 m Hurdles in Shanghai (53.79), Eugene (53.70), Oslo (53.60), Paris (53.23 NR), and London (53.07 NR). Hejnová also won races in Des Moines (54.41), Prague (54.55) and Ostrava (53.32). Hejnová secured maximum points for Czech Republic in the European Team Championships First League in Dublin by winning the 400 m in 51.90 seconds. On 15 August 2013 in Moscow, she became World Champion over 400 m Hurdles with a new Czech record (52.83 NR).