Background and aim: In the last three decades, spirometry has become one of the main diagnostic tools in pulmonology. But different nomograms in different references has brought about challenges. The aim of this study was to obtain normal ranges of spirometry parameters in the people living in Kurdistan province.

 Materials and Methods: This was a discriptive study, and included all 15 to 64 years old people of Kurdistan province. Sampling method was random and sample size encompassed 1589 people. Weight, height and demographic data of the subjects were recorded in check lists. Then spirometry was performed under standard conditions. Data were analyzed with SPSS soft ware using descriptive statistics including frequency, mean and standard deviation.

 Results: The results of this study showed that the mean value for forced vital capacity (FVC) was 3.6 liters (CI=0.96%) 4.33 Lit for men (CI=0.89%), and 3 Lit for women (CI=0.46%). The mean FEV₁ values were 3.74 (CI=0.82) and 2.61(CI=0.53) for men and women respectively.

 Conclusion: According to the results of this study, it seems that the values for FEV₁ are as the same as those of other references, but the values for FVC are lower. Therefore the normal ratio of FEV₁/FVC increases, and should be considered while interpreting spirometry results.