The paper presents Serbian dialect lexical materials collected on the basis of a questionnaire of the “Serbo-Croatian dialect Atlas” in the villages of Western Bosnia. This territory is the area of distribution of Western dialects of the East Hercegovina dialect, which is the basis of the Serbian literary language. The presented questionnaire demonstrates the basic vocabulary of one of the dialects of this type, which in the future is planned to be compared with the dialects of other types in order to identify common and differential lexical features of various Serbian dialects. The vocabulary of the described dialect is characterized by a significant affinity to the literary language and dialect synonyms coexist with literary words. The vocabulary of the dialect is characterized by the preservation of Slavic archaisms, displaced in the more Eastern territories by new words (željezo ‘iron’, zdjela ‘bowl, deep plate’, жлица ‘spoon’, mrkva ‘carrot’, gra ‘bean’, lače ‘pants’, plata ‘sheet’).