Hepatitis C virus (HCV) is the most common chronic disease in all world society. It is often a silent disease and causing no symptoms until much of the liver has been damaged. In this book we built a system dynamics model for the different life cycle stages of the HCV disease including the related factors using VENSIM PLE software. This dynamic model gave the chance to take different measures to prevent or minimize the occurrence of this disease and provide the ability to decrease the mortality rate from late stage, cirrhosis, by appropriate treatments. The accumulation of the consecutive stages of the HCV disease was an S-shape in the cirrhosis stage. This result suggests a good control on the HCV death rate. The results also discuss the variable sensitivities that affect on the HCV disease and produce some measurements values of the disease stages. The more important factor we discuss in details is the awareness variable, we provide all possible hypothesis that related with other factors to outcome some realistic behavior of the disease cycle with its affecting factors.