The incidence of acute and chronic rejection has declined with improvement of immunosuppression regimens in liver transplant recipients. The CD44 protein belongs to a large family of type I Trans membrane glycoproteins and expressed on the surface of most vertebrate cells and is an important receptor for the components of extracellular matrix. The study evaluated if the serum level of CD44 had a value in diagnosis of acute rejection depending on proved rejection by liver biopsy. The patients were recruited from ASCOT from May 2017 to December 2018. They were 20 adults with Post LDLT with elevated liver function tests and were reviewed. The results showed that serum level of CD44 was significantly lower in the rejection group in our study in patient with post liver transplantation. There was highly significant difference between controls & patients \as regards serum level of CD44. Negative correlation between serum levels of CD44, WBCs & AST. There was highly significant difference between patients with different pathological findings as regards serum level of CD44. The best cut off point for serum level of CD44 as a marker of rejection was found ≤ 44ng/ml with sensitivity of 85% and specificity of 95% in diagnosis of acute cellular rejection.