The aim of the experiment was to determine the optimal presowing treat­ment for breaking seed dormancy of Japanese raisin tree (Hovenia dulcis Thunb.), a very rare exotic species introduced to the Mediterranean parts of Serbia and Mon­tenegro. Three pretreatments are applied: mechanical scarification and chemical scarification (conc. H2SO4) lasting for 5 and 120 minutes. The best treatment was the longer chemical scarification, which confirmed the dormancy of the seedcoat.