Hillegonda (Hiltje) Maas-van de Kamer (born 9 December 1941) is a botanist at the Institute of Systematic Botany at Utrecht University. She is the wife of Professor Paul Maas and together they have published many papers. She is a specialist in the flora of the neotropics. The Annonaceae and saprotrophic plants from the neotropics, such as the Burmanniaceae, are two major areas of research.