The Hopf bifurcation is analyzed for a new type of three-dimensional autonomous chaotic system，of which the chaotic attractor belongs to the category of conjugate Chen attractors. A new four-dimensional autonomous hyperchaotic system is constructed based on this chaotic system by introducing an additional controller. This hyperchaotic system with one parameter presents hyperchaotic behavior over a range of parameter values. The analysis of Lyapunov exponents and bifurcation diagram demonstrates the evolution process from periodic orbits， quasi-periodic orbits to chaos， and further to hyperchaos as the parameter increases.