The complex bursting of a kind of cortical pyramidal neuron model, was analysized. The roles of electrophysiological parameters under different cases were discussed, and the rich dynamical properties were obtained in the complex bursting of the pyramidal neuron,such as the period adding bifurcation and period doubling bifurcation of InterSpike Intervals(ISIs). From the model results,we can get a further understanding of the rich firing patterns and rhythm coding which are contained in the complex burst firing of cortical pyramidal neuron.