Virtualization is not a new concept in computer science. It has been used since the middle of the sixties and now software companies has interested in this technology. Virtualization is used in server side to maximize the capacity and reduce power consumption. This thesis focuses on virtualization in embedded system. The technology uses a hypervisor or a virtual machine monitor as a software layer that provide the virtual machine and to isolate the underlying hardware. One of most interesting issue is that is supports several operating system and applications running on the same hardware platform and the hypervisor has complete control of system resources. The company Open Kernel Labs is one of the leading providers of embedded systems software virtualization technology and OKL4 is one of theirproducts, which is based on L4 family of second-generation microkernel’s. In this thesis, we will evaluate the kernel contains, the performance, the security and the environment of the OKL4. Finally we conclude the advantages and disadvantages of the product and technology.