The right atrium pressure load is increased in pulmonary stenosis (PS) that is a congenital anomaly and this changes the electrophysiological characteristics of the atria. However, there is not enough data on the issue of P wave dispersion (PWD) in PS.Forty-two patients diagnosed as having valvular PS with echocardiography and 33 completely healthy individuals as the control group were included in the study. P wave duration, p wave maximum (p max) and p minimum (p min) were calculated from resting electrocardiography (ECG) obtained at the rate of 50 mm/sec. P wave dispersion was derived by subtracting p min from p max. The mean pressure gradient (MPG) at the pulmonary valve, structure of the valve and diameters of the right and left atria were measured with echocardiography. The data from two groups were compared with the Mann-Whitney U test and correlation analysis was performed with the Pearson correlation technique.There wasn't any statistically significance in the comparison of age, left atrial diameter and p min between two groups. While the MPG at the pulmonary valve was 43.11 +/- 18.8 mmHg in PS patients, it was 8.4 +/- 4.5 mmHg in the control group. While p max was 107.1 +/- 11.5 in PS group, it was 98.2 +/- 5.1 in control group (p=0.01), PWD was 40.4 +/- 1.2 in PS group, and 27.2 +/- 9.3 in the control group (p=0.01). Moreover, while the diameter of the right atrium in PS group was greater than that of the control group, (38.7 +/- 3.9 vs 30.2 +/- 2.5, p=0.02). We detected a correlation between PWD and pressure gradient in regression analysis.P wave dispersion and p max are increased in PS. While PWD was correlated with the pressure gradient that is the degree of narrowing, it was not correlated with the diameters of the right and left atria.