This article examines the study of the speech culture of 103 Slovene tour guides employing tourism discourse in their mother tongue by using participant observation, active listening, and linguistic analysis. Besides the knowledge of foreign languages, for tourism guides the mother language skills in the current study of the Slovene language play a significant role. However, it turned out that also, in the education of tour guides, this area is not regulated systematically and is not a part of tour guides' education modules in Slovenia, but left to the individual's life-long learning process or to the acquired level of knowledge during formal schooling in secondary or grammar schools. Consequently, tour guides are not yet trained systematically in speech culture. It should be observed that in the analyzed speech situations the usage of dialects, which can contribute to the quality of the tourist experience in some speech situations, was not appropriate. The guides' language during their presentations and guidance had stronger or weaker traces of dialects and they also often made some typical pronunciation mistakes, such as pronouncing the incorrect syllable, the incorrect pronunciation of the l-participles, or the incorrect pronunciation of some proper name also in speech situations that required the use of standard language instead of dialects. All this can result in the negative tourist experience, especially when tourists are more demanding.