ABSTRACT Aim: To study the biochemical changes in the oral fluid of individuals with generalized periodontitis living in different environmental conditions. Materials and Methods: In order to investigate biochemical changes in the oral liquid of people diagnosed with generalized periodontitis associated with the impact of Cd, we examined 113 people aged from 20 to 59 years. Generalized periodontitis was detected in 83 (73,45%) patients: initial – 19 (22,9%) cases, stage I – 32 (38,55%), and stage II – 32 (38,55%). All the examined individuals were further divided into two groups. The first group (n=52) consisted of people from certain areas in the Ivano-Frankivsk region of Ukraine with elevated Cd content. The second group (n=61) included individuals who lived in areas of the Ivano-Frankivsk region where the Cd content in the environment (soil) did not exceed the maximum permissible concentration. We estimated the content of calcium (Ca), inorganic phosphorus (Pi), and the hydroxyproline level in the oral liquid of the enrolled subjects. Results: A decrease in Ca content in the oral liquid of patients with generalized periodontitis was found, which was accompanied by an increase in Pi and hydroxyproline, observed in both study groups as compared to controls. These changes were associated with the progression of generalized periodontitis severity. Conclusions: The obtained results indicate a certain similarity in the biochemical changes of oral fluid among individuals residing in areas with differen environmental conditions, thus requiring further research.