One of the career areas included in the field of Biomedical Engineering is the application of engineering system analysis: physiological modelling, simulation and control. This paper describes a Virtual Laboratory for the analysis and the study of Human circulatory system. The Virtual Laboratory is based on the compilation of several mathematical models described in the literature. Presented application has been build using MATLAB/ Simulink and EJS, so it combines good computation capabilities and it is completely interactive. The Virtual Laboratory is designed in order to understand the operation of the circulatory system under normal conditions, and to predict circulatory variables at different levels of stimuli and conditions.