Introduction: It has been reported that COVID-19 may cause severe endothelial damage. Pulmonary Artery Stiffness (PAS) is a strong predictor of right ventricular function. PAS can reveal important information about the endothelial functions of the pulmonary bed. In this study we aimed to elucidate the possible effect of COVID-19 on PAS. Materials & Method: The study was performed by measuring PAS values with transthoracic echocardiography in 130 patients, 60 of whom had COVID-19 and 70 were controls. COVID-19 patients with positive polymerase chain reaction (PCR) test results were included in the study 3-6 months after their positivity. Results: When the Maximal frequency shift (MFS) (Hz) results were examined, no significant difference was observed between the patient and control groups (2764 ± 279.24 and 2664.8 ± 673.91 p=0.340, respectively). There was a significant difference between the patient and control groups in favor of the patient group in pulmonary acceleration time (PAT) (msec) results (93.18 ± 14.99 and 126.1 ± 17.58, respectively, p<0.001) . There was a significant difference between the patient and control groups in favor of the patient group in pulmonary artery stiffness (PAS) (Hz/msec) results (30.28 ± 5.07 and 21.57 ± 7.04, respectively, p<0.001). Conclusion: It is possible that COVID19 may have adverse effects on the pulmonary artery wall and bed. As a result of endothelial damage due to COVID-19, an increase in PAS values can be observed.