To investigate the expression of suppressor of cytokine signaling 3（SOCS-3）in Balb/c mice brain and the association with brain lateralization, the paw preference test was used to select right-pawed, left-pawed mice. The SOCS-3 expression level was detected by RT-PCR. The results showed that,（1）The SOCS-3 expression level in right cortex was higher than that in left cortex of left-pawed mice (P＜0.05) and it was also higher in the left cortex of right-pawed mice than that in the left cortex of left-pawed mice(P＜0.05),（2）The SOCS-3 expression level in right hippocampus was higher than that in the left hippocampus of left-pawed mice (P＜0.05) and it was also higher in the left hippocampus of right-pawed mice than that in the left hippocampus of left-pawed mice(P＜0.05),（3）The SOCS-3 expression level in hypothalamus of right-pawed mice was higher than that of the left-pawed mice (P＜0.05). These results indicate that the SOCS-3 expression level in Balb/c mice brain is associated with brain lateralization.