Background: MircoRNAs are endogenous, small non-coding RNA molecules that have been recognized as important modulators of gene expression. MicroRNA is considered one of the potential biomarkers of infection and inflammation. Our study aims to identify the potential role of miRNA-155, miRNA-146b, and Procalcitonin (PCT) in the early detection of spontaneous bacterial peritonitis in cirrhotic liver patients. miRNA-155 and 146b are molecular biomarkers , while procalcitonin is a serum marker in ascites patients complicated with Spontaneous Bacterial Peritonitis (SBP) . Methods: This study was conducted on 199 patients, 101 of them have ascites complicated with spontaneous bacterial peritonitis, and 98 patients without spontaneous bacterial peritonitis (control group). Ascitic fluid samples were collected from patients with SBP undergoing paracentesis at National Hepatology Institute in Egypt. MicroRNAs were determined in the serum using qPCR (quantitative polymerase chain reaction), while procalcitonin has been assessed in serum samples using ELISA (Enzyme-linked immune assay) technique. Results: Serum levels of miRNA-146b & miRNA-155 were significantly higher (p<0.001) in spontaneous bacterial peritonitis patients (79.2% and 97.0% respectively) than ascites patients (17.3% and 7.1%, respectively). Furthermore, the serum level of procalcitonin was significantly higher (p<0.001) in spontaneous bacterial peritonitis patients than that in ascites patients (68.3% and 27.6%, respectively). Conclusion: miRNA-155, miRNA-146b and procalcitonin can be used as early markers for the detection of SBP in hepatic patients with ascites.