Simulation modeling is becoming a very familiar tool used for handling healthcare systems’ problems and issues.  Most applications considered using individual simulation methods only. The complexity of healthcare systems is derived from its complex structure consisting of queues and flows concept, and human behaviors and decision making. Individual methods are incapable of capturing all of these elements in one paradigm. In such cases, the more model assumptions are used, the less realistic models may result. However, discrete event simulation and agent based simulation methods together may be capable of capturing such concepts and details. In this paper, a discrete event – agent based hybrid approach for modeling healthcare systems is proposed. Then a description and validation of a case study for a Radiology Center is presented.