Klaas van Oostveen was born 1752 in Amsterdam, North Holland, Netherlands to Seger van Oostveen (c1720) and Antje van den Berg . He married Hendrikje Olij (1759) in Amsterdam, North Holland, Netherlands.
Also known as Claas van Oostveen. Probably born in late 1751 or early 1752.
Children
| Name | Birth | Death | Joined with |
| Antje van Oostveen (1780-1866) | 1780 Amsterdam, North Holland, Netherlands | 5 July 1866 Amsterdam, North Holland, Netherlands | Johannes Franciscus Velthuijs (c1779-1847) |
| Zegert van Oostveen (1783-1857) | 6 November 1783 Amsterdam, North Holland, Netherlands | 12 December 1857 Amsterdam, North Holland, Netherlands | Barbara de Looper (1782-) |
| Joanna van Oostveen (1785-) | |||
| Catriene van Oostveen (1787-) | |||
| Elisabet van Oostveen (1793-) | |||
| Hendrikje van Oostveen (1796-) | |||
Residences