ObjectivesNasal septum deformation (NSD) contributes to the occurrence of upper respiratory tract diseases in around 45-55% of Poland's population. The evaluation of frequency of occurrence and type of nasal septum deformation among randomly chosen representatives of the Szczecin and surrounding area population was the aim of this study.MethodsNSD was assessed in 235 patients (123 male, 112 female) aged 5-60. Mladina's classification system was used for the evaluation.ResultsDeformations of nasal septum were found in 43% of the examined subjects. Type 3 of NSD dominated (12.4%), while types 2 and 1 were found in 10.3% and 4.2% of the subjects, respectively. 9.2% of the patients showed type 5 of deformation, while types 6, 4, and 7 were found in 1.3%, 3.2% and 2.7% of the patients, respectively.ConclusionsStraight nasal septum was found in females more often than in males, mostly on the left side. Associations between NSD, on one side, and age, sex, and traumas, on the other were found. NSD influenced the quality of respiration and frequency of upper respiratory tract diseases in the examined subjects.