Objective: P-wave dispersion is associated with inhomogeneous and discontinuous propagation of sinus impulses. The aim of this present study was to investigate the impact of P-wave dispersion in children with stable asthma. Materials and Methods: In this cross-sectional study, the study group consisted of 20 children (12 boys, 8 girls) with stable asthma and mean age of 7.7 ± 2.0 years. During the study, these patients were treated with low dose inhaled corticosteroids for at least six months. Control group consisted of 20 healthy children matched by same sex and age population. Age, weight, height, echocardiographic values, P-wave maximum duration and P-wave dispersion were compared between asthmatic and healthy children. P - wave duration was calculated in 12-leads of the surface electrocardiography. The difference between P maximum and P minimum durations was defined as P - wave dispersion. The obtained results were compared by independent samples t test and Mann-Whitney U test. Correlations for P- wave dispersion were calculated using Pearson test. Results: P-wave maximum duration is slightly increased in patients with stable asthma (0.092 ± 0.017 ms) as compared with healthy controls (0.083 ± 0.011 ms) (p=0.07). We found significant correlation between P-wave dispersion and age (r=0.40, p=0.01), weight (r=0.41, p=0.008) and height (r=0.41, p=0.008). Conclusion: P-wave maximum duration is slightly increased and P- wave dispersion is correlated with age, weight and height in children with stable asthma.