Abstract: A novel model for dynamical marketing system is developed which takes into account the psychological factors. The model can be easily modified and extended, resulting in a unmber of forms. The dynamical behavior is analyzed and a real case is also given for illustration. It is shown that the complicated behavior of bifurcation and chaotic motion does exist in such a simple economic model. These phenomina arise from the system structure and its parameters rather than any external random disturbances.