Sven August Heintze was born on 26 September 1881 to Fredrik and Kerstin (née Svensson) Heintze in Skurup, Skåne. He had a younger sister, Anna Maria (b. 1889). He enrolled as a student at Lund University in 1901. He graduated in 1906, and earned his doctorate in 1913. His first position was as a teacher at Uddevalla kommunalgymnasium. Heintze died on 6 May 1941 in Stockholm, and is buried in the Skurups Norra Kyrkogård ("Skurup's Northern Cemetery").
He is known for his work on the classification of cormophytes, particularly the Ranuculaceae family.