Niels Fabian Helge von Koch (25 January 1870 – 11 March 1924) was a Swedish mathematician who gave his name to the famous fractal known as the Koch snowflake, one of the earliest fractal curves to be described.

His father, Richert Vogt von Koch (1838–1913) was a Lieutenant-Colonel in the Life Guards of Horse of the Swedish Army.

He was enrolled at the newly created Stockholm University College in 1887 (studying under Gösta Mittag-Leffler), and at Uppsala University in 1888, where he also received his bachelor's degree (filosofie kandidat) since the non-governmental college in Stockholm had not yet received the rights to issue degrees.

[1] He described the Koch curve in a 1904 paper entitled Sur une courbe continue sans tangente, obtenue par une construction géométrique élémentaire ("On a continuous curve without tangents constructible from elementary geometry").

[2] He was an invited speaker at the International Congress of Mathematicians in 1900 in Paris with talk Sur la distribution des nombres premiers ("On the distribution of prime numbers")[3] and in 1912 in Cambridge, England, with talk On regular and irregular solutions of some infinite systems of linear equations.