Niek Kimmann (born 20 May 1996) is a Dutch BMX racing cyclist.
Kimmann was born in Lutten. He won the Junior Men during the 2014 UCI BMX World Championships. In August 2014 Kimmann together with Wiebe Scholten won a bronze medal in the team boys event of the 2014 Summer Youth Olympics.
On 25 July 2015 he won the Elite Men of the 2015 UCI BMX World Championships in Zolder, Belgium, at age 19. He came in second during the Time Trial the day before. Kimmann became the second Dutch BMX World Champion, after Robert de Wilde, who won in 1999.
His younger brother, Justin Kimmann, is also a BMX rider and competed in the junior events at the 2016 UCI BMX World Championships.