Background: Orsomucoid protein A (ORM) is a major acute-phase protein. Serum ORM (se-ORM) protein A elevates in infections, malignancies, and autoimmune diseases. Urinary ORM (u-ORM) protein A is more accurate and less invasive marker of inflammation. Elevated u-ORM was associated with pathomechanism factors related to psoriasis such as endothelial dysfunction; however, the clinical significance of it has not been explored yet. Aim: To evaluate se-ORM/u-ORM protein A and urinary orsomucoid protein A/urinary creatinine (u-ORM/u-CREAT) in patient with psoriasis and their relations to severity of the disease. Methods: This case-control study was conducted at Dermatology and Andrology Department; 35 psoriasis patients and 35 age-and sex-matched healthy controls were included. They were subjected to history taking and general and dermatological examination. Psoriasis severity was assessed by Psoriasis Area and Severity Index (PASI) score. Measurement of se-ORM/u-ORM protein A using ELISA and u-ORM/u-CREAT using colorimetric method.Results: Highly significant difference between psoriasis patients and controls regarding u-ORM protein A level (p value = 0.01). It was also higher in severe cases than moderate and mild ones and higher in moderate than mild cases (p value 0.001, 0.001, and 0.004, respectively). There were significantly higher u-ORM/u-CREAT (p ˂ 0.001) levels in psoriasis patients than in controls. Also, significantly higher U-ORM/u-CREAT levels were found in severe psoriasis cases than in mild and moderate cases (p = 0.003 and 0.006, respectively). While the se-ORM levels showed no significant differences between the studied groups.Conclusion: u-ORM/u-CREAT is a highly sensitive, easily available, and new inflammatory biomarker of psoriasis which correlates to the disease severity.