The aim of this work is to give an up-to-date and methodical overview of the oldest toponymic stratum on Croatian territory. This stratum consists of geographical names that existed on Croatian territory before the arrival of Slavic tribes in 6th / 7th century. More than 300 proper names of places, bodies of water, islands, mountains and other geographical objects which are attested in ancient sources, in text and inscriptions older than the 7th century are studied for this purpose. The toponomastic dana is analyzed on several levels which results in lexicon of the Croatian pre-Slavic toponyms. Each toponym has been analyzed philologically – ancient sources have been reviewed to verify the attestations of the toponyms and differences in attestations have been accounted for; geographically, historically and archaeologically as well as linguistically – older etymologies of toponyms have been reconsidered and some new ones have been adduced. For the toponyms with continuity in Croatian as loanwords from (Vulgar) Latin into Croatian the phonological adaptations have been stated as well. After the individual toponyms are analyzed in this way, the toponyms are grouped according to their toponomastic category (oikonyms, hydronyms, nesonyms, oronyms and other geographical names) and according to their chronological and linguistic stratification (pre-Indo-European, „Illyric“, Celtic, Greek and Roman). Toponyms with continuity in Croatian are seperately accounted for, linguistically and extra-linguistically: their phonological and morphological adaptations from Vulgar-Latin to Croatian are described and some of their extra-linguistic characteristics are singled out as conditions under which the onomastic continuity is preserved. These toponyms with onomastic continuity bear witness to the earliest contacts between Roman and Slavic peoples and are the oldest Croatian linguistic monuments.