Interpretation of the spirometric results in young children aged 3 years and onward was a difficult task, because existing reference values usually covered age range of 7–18 years. Recently two big studies concerning 'all ages' reference equations were published: the study of The Asthma UK Initiative (Stanojevic et al. AJRCCM 2009) and the so called GLI2012 values (Quanjer et al. ERJ 2012); both providing equations with LMS approach for spirometric reference values for age range of 3–95 years. The aim of the study was to test the applicability of the new sets of equations in a group of healthy Polish children of Caucasian descent. The analysis was performed on a data gathered from children admitted to outpatient department for diagnostic reasons. Children performed impulse oscillometry (IOS) measurements and spirometry. Elevated value of oscillometric resistance at 5 Hz (R5) eliminated children from analysis as well as forced expiratory time less than 1.5 s. Final analysis was performed on results obtained from 142 children aged 4–10 years. Z-scores and percent of predicted values were calculated for FEV1, FVC and FEV1/FVC using both sets; additionally z-score and percent predicted was also calculated for FEV0.75/ FVC using Stanojevic's equation. The distribution of all calculated z-scores was normal. For FEV1/FVC mean ± SD of z-score was 0.01 ± 0.80 using GLI2012 and -0.15 ± 0.79 using Stanojevic's set. Mean value of percent predicted values using GLI2012 was 100.2 ± 5.5% for FEV1/FVC, 107.4 ± 9.4% for FEV1 and 106.6 ± 10.1% for FVC. Our results confirm applica-bility of the new sets of reference values in young Caucasian children from Poland and point out the potential diagnostic value of FEV0.75/FVC.