Oswalt Kolle (2 October 1928 in Kiel – 24 September 2010 in Amsterdam^[1]) was a German-Dutch sex educator, who became famous during the late 1960s and early 1970s for his numerous pioneering books and films on human sexuality. His work was translated into all major languages, while his films found an audience of 140 million worldwide. In his 1997 book Open to Both Sides he came out as bisexual.^[2]

He was awarded the Magnus Hirschfeld Medal in 2000.

He had lived in the relatively more sexually liberal city of Amsterdam, Netherlands since the 1970s with his three children to escape harassment of his family by conservative German journalists, and was also a Dutch citizen. His wife died in 2000.^[2]