Spa tourism in Serbia has a considerable tourist potential. Today there is a strong competition on the tourist market, particularly among destinations in spa tourism. Competitiveness of any tourist destination, in particular a spa tourism desti¬nation, greatly depends on key attributes of tourism supply. This paper includes the result of a study which was carried out in order to improve tourists' perception of the importance of the attributes of tourism supply in Vrnjacka Banja. By reviewing the literature, attributes were extracted and grouped into factors in order to decide which groups had the greatest importance in the minds of spa tourists. There were six factors in total. After that and based on t-test, a statistically significant difference between the tourists who plan to visit Vrnjacka Banja again and to recommend this tourist destina¬tion and those who do not was determined according to their attitudes towards these factors. Finally, using ANOVA test, the study proves a statistically significant differ¬ence related to the attributes depending on how long the tourists stayed in Vrnjacka Banja. By recognizing the key attributes of a spa tourist destination in the spa tourists' perception, organizations and individuals who are responsible for the development of tourism will be able to form a supply which suits tourists' needs best, while achieving a high-level competitiveness on the tourist market at the same time.