Josephina Johanna "Jopie" Troost (born 19 September 1942) is a retired Dutch swimmer who competed at the 1960 Summer Olympics in the 4 × 100 m freestyle relay.
A medal favorite, the Dutch team was disqualified in the heats for a premature start by Sieta Posthumus.
Troost was part of 4 × 100 m freestyle relay teams that set three national records in 1958.