[en] The semi-quantitative determination of salicin by TLC described in the German Pharmacopoeia (DABX) does not separate salicin from picein, another phenolic glycoside of some willow species. In this paper we propose to combine the use of both an adequate mobile phase and a suitable reagent (vanillin reagent instead of sulfuric acid-thymol) for an unambiguous determination of the amount of salicin..