| Birth Date: | 1946 7, df=y |
| Birth Place: | Amsterdam, the Netherlands |
| Height: | 180 cm |
| Weight: | 72 kg |
| Sport: | Rowing |
| Club: | Nereus, Amsterdam |
| Show-Medals: | yes |
Liesbeth Simone Vosmaer-de Bruin (de Bruin, born 9 January 1946) is a retired Dutch rower. She competed at the 1976 Summer Olympics in the coxed fours, together with Hette Borrias, Myriam van Rooyen-Steenman, Ans Gravesteijn and Monique Pronk, and finished in fifth place. She won a European title in this event in 1973, with Hette Borrias, Myriam van Rooyen-Steenman, Yvonne Vischschraper and Liesbeth Pascal-de Graaff. At the world championships, her team was fifth in 1975 and seventh in 1977 and 1978.