Abstract
In this paper, a new four-dimensional continuous-time autonomous hyper chaotic system, which has a complicated four-wing attractor, is formulated by adding a linear controller to a chaotic system. The existence of the hyper chaos is verified with bifurcation analysis and Lyapunov exponent spectrum. The bifurcation routes from periodic, chaotic to hyper chaotic evolutions are observed simultaneously. The essential dynamical behaviors are demonstrated not only by numerical simulation but also by circuit realization.