| Johannes Walaeus | |
| Birth Date: | 27 December 1604 |
| Birth Place: | Koudekerke, Walcheren, Dutch Republic |
| Death Place: | Leiden, Dutch Republic |
| Nationality: | Dutch |
| Fields: | Medicine |
| Workplaces: | University of Leiden |
| Education: | Leiden University (M.D., 1631) |
| Doctoral Advisor: | Otto Heurnius |
| Notable Students: | Thomas Bartholin |
Johannes Walaeus (born Jan de Wale; also known as Johannes de Wale; 1604–1649) was a Dutch physician and illustrious professor at the Faculty of Medicine in Leiden University.He was graduated Doctor of Medicine in 1631, when he defended his dissertation, entitled Disputiatio medica de febribus at Leiden University.[1] Two years after that, he was nominated Professor extraordinarius. In 1648, he was offered full professorship at Leiden University. Johannes Walaeus was a son of the theologian Antonius Walaeus.