Jaroš Griemiller (Třebsko) was a Czech alchemist and author of Rosarium Philosophorum, the first in the Czech-translated medieval alchemical manuscript. This document is the only thing we know about him. He worked under Wilhelm von Rosenberg in the 1570s and carried the Rosarium to him. He completed the manuscript work in 1578 while working in Český Krumlov.

The Rosarium Philosophorum shows that alchemy was practiced in Bohemia before the court of Emperor Rudolf II settled in Prague. The work is a Czech translation of a medieval alchemical dissertation. Griemiller was probably family of officer Pavel Griemiller z Trebska (died in 1593). Griemillers friend, the astronomer and alchemist Bavor ml. Rodovský z Hustiran (about 1526-1592) may have been a source of inspiration for him. Griemiller contributed to the benefactor of the alchemist research, nobleman and diplomat Vilém z Rožmberka (1535-1592). This book by Griemiller is richly illustrated and bound in gold-decorated leather. Hence it is speculated that it was intended for the Rožmberk library. The extraordinary quality and art of the illustrations suggest that Jaroš Griemiller himself was an artist or was assisted by a painter employed by the Rožmberk court.

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