The characteristics of the acoustic response of AⅠneurons to the frequency of pure tone were investigated with extracellularly recording. The experimental results showed that the tuning curves of AⅠneurons could be classified into “V”, “W”, and “U” types. Q10 values and Q30 values of AⅠneurons increased with increasing of the characteristic frequencies (CFs) of these neurons. The results also showed the topographical distribution of the CFs of neurons in AⅠcortex. Generally the neurons with high CFs laid in the rostral part of AⅠ, and the neurons with low CFs laid in its caudal part. These results indicated that AⅠneurons with high CFs had more powerful frequency selectivity ability than that with low CFs, and that the frequency range of acoustic response of AⅠneurons widened with increasing of CFs of these neurons. The topographical distribution of the CFs in AⅠindicated that the coding on frequency of sound stimulation accorded with the rule of place coding.