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The effects of sodium salicylate (NaSA) on the expressions of γ-aminobutyricacid (GABA) and glutamate (Glu), andauditory response properties of the inferior colliculus neurons in mice were studied. Thirty-six Kunming mice were divided into threegroups: control group (saline injection); NaSA group (NaSA 450 mg/kg, i.p., each day for 15 d); NaSA + lidocaine group (NaSA 450 mg/kg + lidocaine 10 mg/kg, i.p., each day for 15 d). The expressions of GABA and Glu were examined with immunohistochemical method.The intensity-rate function, intensity-latency function and frequency-tuning curve were determined with extracellular electrophysiologicalrecording. Results are as follows: (1) The expression of GABA in the NaSA and NaSA + lidocaine groups decreased remarkablycompared with that in the control group; there was no noticeable difference between the NaSA and NaSA + lidocaine groups. Theexpression of Glu in the NaSA group increased significantly compared with that in the control and NaSA + lidocaine groups. Nodifference in the expression of Glu was found between the control and NaSA + lidocaine groups. (2) In NaSA group, the intensity-rate function displayed a non-monotonic pattern, rising at low intensity and descending at high intensity; the tip of frequency-tuning curvesbecame broad after administration of NaSA. (3) The changes in intensity-rate function and intensity-latency function were not evidentand the tips of the frequency-tuning curves sharpened in the NaSA+lidocaine group. These results suggest that administration of NaSAincreases the expression of Glu-positive neurons and reduces that of GABA-positive neurons in the inferior colliculus. NaSA changesthe auditory response properties of the inferior colliculus and lidocaine can reverse these changes.