A toolbox for simulation of hybrid systems in Matlab/Simulink: Hybrid Equations (HyEQ) Toolbox. This paper describes the Hybrid Equations (HyEQ) Toolbox implemented in Matlab/Simulink for the simulation of hy- brid dynamical systems. This toolbox is capable of comput- ing approximations of trajectories to hybrid systems given in terms of differential and difference equations with con- straints, called hybrid equations. The toolbox is suitable for the simulation of hybrid systems with different type of trajectories, including those that are Zeno and that have multiple jumps at the same instant. It is also capable of simulating hybrid systems without inputs, with inputs, as well as interconnections of hybrid systems. The structure, components, and usage of the simulation scripts within the toolbox are described. Examples are included to illustrate the main capabilities of the toolbox.