Johannes Magirus (c. 1560 – 1596) was a German physician and natural philosopher. He was born at Fritzlar about 1560; his background was Lutheran. He studied at the University of Padua, and took a medical degree at the University of Marburg in 1585.
- Physiologiae Peripateticae libri sex (1597). This was a textbook treatment of Aristotelian philosophy, and was still in use 50 years later. It was employed to teach physics in the early years of Harvard College. Isaac Newton was introduced to natural philosophy by this work of Magirus and one of Daniel Stahl. It used the works of: Hermolao Barbaro, Gasparo Contarini, Thomas Erastus, Philipp Melanchthon, Arcangelus Mercenarius, Francesco Patrizzi, Julius Caesar Scaliger, Jakob Schegk, Johannes Velcurio, Francesco Vimercato, and Jacopo Zabarella.