Background and Objectives: Trichomonas tenax is a protozoan, participating in the human oral microflora. It is considered as a potential paradontopathogen. This microorganism is also reported in the respiratory tract. We aimed to analyze the available literature about the prevalence of Trichomonas tenax in the population affected by periodontal disease. Materials and Methods: Тhe searching with keywords: ,,Trichomonas tenax” and “periodontal diseases’’ in Scopus, PubMed and ScienceDirect databases was able to identify several systematic reviews and original articles until July 2023. All studies with suffering from periodontal disease people, mentioned year of publication, country, specified detection methods, total number of tested samples as well as the percentage of those infected with Trichomonas tenax were included. Irrelevant articles were excluded. Results: We found 137 studies, but only 64 studies about distribution of Trichomonas tenax in patients with gum disease underwent qualitative analysis. The highest number of studies have been conducted in Iran, Poland and Iraq. Different methods have been used to detect the unicellular organism, each with different specificity and sensitivity. Conclusions: Interest in Trichomonas tenax has grown considerably since 2000. Because of its association with periodontal disease, Trichomonas tenax role in the inflammatory process shouldn’t be overlooked.