Aim To explore and establish an influence of biometeorological conditions on the occurrence of spontaneous pneumothorax (SP) in the city of Kragujevac (Serbia) in a five-year period. Methods According to the type of series of cases, this was a retrospective,non interventional study. The data collected from the medical records and operative protocols of the Thoracic Surgery Department in the period between 01.01.2005 and 31.12.2009, as well as the data on daily biometeorological phases for the Kragujevac city obtained from the Hydrometeorological Service of Serbia, and afterwards a comparative analysis of the data were performed. Results A total number of 159 patients with spontaneous pneumothorax were hospitalized. Most patients were treated in 2009(55, 34.6%), least in 2005 (22, 13.8%). Most cases occurred in March (20, 12.6%), on Tuesdays (33, 20.7%), and in the biometeorological phase 2 (0.15 SP/day). The least number of cases occurred in September (9, 5.7%), on Saturdays (6, 3.8%) and in phase 8 (0.04/day) (p<0.01). Conclusion There was an evident biometeorological influence onthe occurrence of spontaneous pneumothorax in our area, so mostcases were in the phase with sunny weather (atmospheric pressurefalling, air temperature and moisture rising), while the lowestnumber was in the phase with a fall of atmospheric pressure, moistureand air temperature. The results of this research suggest a necessity of further investigations on this field