Johann Winter von Andernach (born Johann Winter; 1505 – 4 October 1574) was a German Renaissance physician, university professor, humanist, translator of ancient, mostly medical works, and writer of his own medical, philological and humanities works.

He probably came from a poor family and attended the town school in Andernach, then part of the Electorate of Cologne.

There he met Lambertus Hortensius [nl] who was a teacher at Utrecht's Hieronymus school.

When the name "Winter" was translated into Italian and Latin, the "W" was replaced by "Gue" or the "Wi" replaced by "Gui," giving rise to the name "Guenther" and all of its derivatives.

In addition, he also had a kind of pen name: Ionas Philologus, "Johann the philologist."