Jean-Henri-Guillaume Krombach, also known as Johann Heinrich Wilhelm Krombach (16 September 1791 in Moers – 23 February 1881 in Luxembourg City) was a German-Luxembourgian pharmacist and botanist.
He initially worked as an assistant pharmacist in a number of German cities (Soest, Mainz and Aachen), then in 1815 relocated as a pharmacist to Diekirch, Luxembourg.
From 1850 he served as a pharmacist in the nearby town of Ettelbruck.Beginning in 1830 he taught classes in natural sciences at schools in Diekirch and Ettelbruck.