This study assessed platelet activation and its possible contribution to the pathogenesis of liver cirrhosis (LC), hepatocellular carcinoma (HCC) and portal vein thrombosis (PVT). Forty-five patients with LC caused by dual schistosomiasis and viral hepatitis infections were enrolled in the study, 15 had LC only, 15 were complicated with HCC, and 15 were complicated with PVT, in addition to 15 healthy controls. Platelet morphological parameters including platelet count, platelet crit, mean platelet volume (MPV) and platelet distribution width (PDW), as well as platelet activation as evidenced by measuring soluble platelet selectin (sP-selectin) level and the release of beta-thromboglobulin (beta-TG), transforming growth factor beta-1 (TGF-beta1) and platelet derived growth factor-AA (PDGF-AA) were evaluated. The results obtained revealed significant reduction in platelet count, platelet crit and MPV while PDW was significantly increased in all LC patients in comparison to controls. sP-selectin, beta-TG, TGF-beta1 & PDGF-AA revealed significant increase in all diseased groups when compared to control group. Patients complicated with HCC or PVT demonstrated significant increase in the aforementioned parameters in comparison to patients with LC only. Patients with PVT showed significant increase versus HCC patients. These findings indicate that platelet activation is a prominent feature in LC and its serious complications HCC & PVT. This activation can play an important role in the pathogenesis of LC, HCC & PVT in patients with mixed schistosomiasis and viral hepatitis infections. Such patients need careful medical attention and effective treatment. Stabilization of the activated platelets and the dual suppression of PDGF & TGF-beta1 could be new therapeutic strategies against LC and its sequels.