This paper presents the first detailed analysis of the artefacts from the Mousterian level G3 at Vindija Cave and a revision of the artefact analysis for the early Upper Paleolithic levels (j, i) at Velika Pećina, both in Croatia. Combined with an assessment of the artefacts from the crucial G1 level at Vindija, results of these analyses are used to argue that the combination of Middle and Upper Paleolithic elements in the upper G complex at Vindija is not necessarily the result of geological mixing but may well represent a natural cultural assemblage. Some Upper Paleolithic elements are possibly derived from the local Mousterian, while others result from extraneous cultural influences into this region. Interestingly, currently available radiocarbon dates indicate that Neanderthals (Vindija level G1) and early modern humans (Velika Pećina) were penecontemporaneous in this region at ca. 33 ka, or perhaps somewhat earlier if the radiocarbon dates are taken as minimum age estimates. Therefore some Upper Paleolithic tools associated with the Vindija G1 Neanderthals, such as bone points, may result from imitation of or trade with early modern people. While there is external influence on the development of the early Upper Paleolithic in this region, it exhibits a unique character which does not conform to that of classic Western or Central European Aurignacian.