CA3 a-thorny pyramidal neurons have a physiological mechanism for bursting, which has been shown to be an efficient means of inducing synaptic plasticity, but how their biophysical properties influence their bursting firing activities is not yet clear. In this paper, we will focus on discussing the effects of different ion channels on the bursting firing activities of CA3 a-thorny pyramidal neurons. The obtained results show that increasing the conductance of Na-type, Ca and h-ion channels could make soma’s bursting transform to spiking firing; while increasing the conductance of K-type ion channels could change soma’s firing patterns from spiking to bursting. Thus, soma’s firing patterns of the CA3 a-thorny pyramidal neurons are dependent on ion channels, especially on the conductance of each ion channel.