The nonlinear dynamical behavior of a quantum cellular neural network (QCNN) by coupling quantum-dot cellular automata was investigated. The theoretical analysis and simulation for a three-cell coupled QCNN has been done by using the polarization of a quantum-dot cell and the quantum phase as state variables. The com plex and abundant chaotic behaviors can be observed. Chaotic oscillations occur very easily. Two positive maximum Lyapunov exponents have been calculated in ord er to verify the hyperchaotic behavior.