BackgroundThe current study aimed to evaluate the prognostic value of serum amyloid A protein )SAA( protein as a biomarker in diagnosing 2019 novel coronavirus disease )COVID-19( infection. MethodsThe study was conducted on 123 patients with definitive COVID-19 infection referred to Shahid Beheshti and Sina hospitals in Hamedan province, Iran. Five-milliliter blood samples were taken from all included patients and serum was isolated using a centrifuge at 10,000 rpm for 10 minutes. Laboratory tests were conducted, including c-reactive protein (CRP), Erythrocyte Sedimentation Rate (ESR), potassium level, sodium blood test, platelets (PLT), complete blood count (CBC), lymphocyte count, and neutrophil count. The SAA enzyme-linked immunosorbent assay (ELISA) Kit was applied to measure the SAA level in serum samples. Results123 patients included 73 males and 50 females, age ±50. Sixty-six (53.7%) patients had negative CRP while 80 (65%) patients had normal ESR. Potassium levels were not normal among 111 (94.9%) patients. Seventy-seven (63.1%) patients had normal CBC, while 108 (87.8%) patients had neutrophils above the normal range. 94 (97.9%) patients over the age of 50 were positive for SAA. In terms of gender, men were the most frequent patients with SAA. There was a statistically significant relationship between the serum level of SAA and outcomes of patients with COVID-19 (p = 0.0001). 94% of patients with SAA ≤50 were recovered from COVID-19 infection. The sensitivity rate of SAA compared to polymerase chain reaction (PCR) and computed tomography scan (CT scan) tests was 93% and 99%, respectively. Moreover, the accuracy of SAA compared to PCR and CT scan tests was 52% and 96%, respectively. ConclusionResults indicate the SAA is a sensitive, but not specific biomarker in the early detection of COVID-19. The quantitative levels of SAA can be useful in predicting treatment outcomes among patients with COVID-19.