Objective:To study the effects of Bukatoxin on tetrodotoxin-resistant(TTX-R) sodium currents in rat dorsal root ganglion neurons. Methods:The effects of Bukatoxin on TTX-R sodium currents was studied using the whole-cell patch clamp technique in fresh isolated rat dorsal root ganglion neurons. Results:Bukatoxin inhibited TTX-R sodium currents concentration dependently. About 18.72%,27.40% and 59.02% of peak TTX-R sodium currents were inhibited by Bukatoxin at the concentration of 20,40 and 80 μg/ml respectively. The activation curve of TTX-R sodium channel was slightly shifted in depolarizing direction by Bukatoxin and the inactivation curve was shifted in hyperpolarizing direction for about 6 mV. Conclusion:Bukatoxin inhibited the TTX-R sodium currents in dose dependent manner, and changed the activation and inactivation of TTX-R sodium channel. This may count for the modulation of Bukatoxint to the nociception transduction.