This paper presents hardware/software co-simulation and discusses its suitability in the development of real-time systems. Due to the facts that time-to-market challenge has increased the need for shortening the development process, new techniques and methodologies are introduced. A fashionable technique is to use co-simulation environments in the verification phase of a design process. As this technique is being adopted, and the fact that companies from a wide industry area has become using it, real-time issues are becoming relevant. This paper will discuss the use of a co-simulation tool for verification of embedded real-time systems.