Aortic valve stenosis (AS) generates a chronic pressure overload that induces left ventricular hypertrophy (LVH). The aim of this study was to assess the prevalence of the electrocardiographic criteria for LVH in patients with clinically significant AS and to evaluate the relationship between the ECG criteria for LVH and echocardiographic parameters. The clinical data of 95 patients with moderate to severe AS were retrospectively analyzed. Eight ECG criteria for LVH were used and compared to the results of transthoracic echocardiography (TTE). In 59% of patients, at least one of the ECG criteria for LVH was found. These patients had a greater LVMI (142.1 ± 35.6 vs. 124.1 ± 22.5 g/m2 , p = 0.01) and peak aortic jet velocity (4.2 ± 0.8 vs. 3.8 ± 0.9 m/s, p = 0.01) along with smaller aortic valve area (0.72 ± 0.28 vs. 0.86 ± 0.22 cm2 , p = 0.02) compared to patients with a negative ECG for LVH. The ECG parameters had a low sensitivity (6%-36.9%) with a specificity of up to 100%. The Cornell Voltage criteria had the best sensitivity with a specificity of 63.6% and the highest correlation with the LVMI (r = 0.38, p < 0.001). All of the ECG parameters correlated positively with the peak aortic jet velocity as well as with the mean aortic gradient. The electrocardiographic criteria for LVH in patients with moderate or severe AS have a poor sensitivity in identifying LVH confirmed by TTE. The values of the selected ECG criteria for LVH correlate weakly with both the TTE indices of LVH and the markers of AS severity.