The development of embedded chip cooling for 2D and 3D integrated circuits using pumped dielectric refrigerant has gained recent attention due to the ability to manage high heat densities and compatibility with electronics. Recent studies have focused on in-situ thermal and hydrodynamic phenomena (e.g. boiling and bubble dynamics) of two-phase flow boiling at micro-scales. In this paper we focus on the two-phase cooling system design including the cooling capability, size and coefficient of performance (COP). In implementing a two-phase cooling, a system-level computational model for two-phase cooling systems becomes necessary. Therefore, a computationally manageable and accurate one dimensional (1D) system model is described. Furthermore, the model can be easily customized for different two-phase cooling system configurations. By validating the model with experimental data from a two-phase cooling system, it is shown that model can generate accurate results, and therefore, can be used as a tool to study and predict the characteristics and performance of a pumped two-phase cooling systems.