This study aims to building a mathematical model for pneumohydraulic brake system. Creating a pneumohydraulic brake system with a variable transfer attitudes or relation requires really a lot of complex works on modeling transient of such systems. After building the mathematical model it will be solved in order to investigate its final response and stability. It is found that the output pressure values (P1, P2, andP3) are increasing with time; displacements of pistons and may depend on pneumatic and hydraulic properties of the using medium. KEY WORDS: pneumohydraulic brake system, variable transfer attitudes, factor of hydraulic resistance, viscosity factor, brake rigidity, preliminary deformation, and pliability.