Direct-Acting antivirals (DAAs) target intracellular viral replication and have realized high effectiveness for hepatitis C virus (HCV) patients. Now, many kinds of DAA drugs have discovered and the HCV treatment is improving day by day. A popular strategy of HCV treatment is combination of double or triple DAA drugs with different action mechanisms. Mathematical model is used to analyze the dynamics of virus infection and effectiveness of antiviral drugs. For DAA treatment, multiscale model formulated by partial differential equations (PDE) describing both intercellular virus infection and intracellular virus RNA replication is used. However, in general, numerical computation of PDE often converge poorly and is time consuming. So it is somewhat hard to estimate parameters, and we should transform the PDE to easier form in advance of analyzing the model. In our study, we transformed the PDE model to ODE form without any assumption. Thus our ODE model and the previous PDE model are mathematically identical. By this transformation, the time required for numerical simulation is reduced greatly and we can apply some basic analysis methods for dynamical systems of ODEs to the multiscale model.