Angiotensin-converting enzyme inhibitors (ACEIs) reduce arterial stiffness beyond their antihypertensive effect. Studies showed that sulfhydryl ACEIs have the antioxidative potential to improve endothelial function, which might have a clinical effect on arterial distensibility. However, there are no studies that directly compare the effects of sulfhydryl (zofenopril) and non-sulfhydryl ACEIs (enalapril) on arterial stiffness. Therefore, this prospective study aims to compare the effects of enalapril and zofenopril on arterial stiffness and oxidative stress in both short- and long-term treatment of arterial hypertension (AH). Baseline and post-treatment peripheral and central arterial pressure indices, augmentation index (Aix), aortic pulse wave velocity (ao-PWV), serum levels of oxidized low-density cholesterol lipoprotein, LDL and uric acid (UA) were measured. The results showed that acute treatment with zofenopril, in contrast to enalapril, significantly decreased peripheral and central Aix (p < 0.001). Chronic treatment with zofenopril showed a superior effect over enalapril on the reduction of the peripheral systolic arterial pressure with reduction of ao-PWV (p = 0.004), as well as a reduction in peripheral Aix (p = 0.021) and central Aix (p = 0.021). Therefore, this study indicates that zofenopril has beneficial effects on the reduction of arterial stiffness compared to enalapril. It has potent clinical efficacy in AH treatment and further studies should compare its safety and long-term efficacy to other AH drugs that would aid clinicians in treating AH and other various cardiovascular diseases that have arterial stiffness as a common denominator.