Following CNS injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, gliosis. Astrocyte-rich gliosis relates with up-regulation of GFAP and CD81, and eventually becomes physical and mechanical barrier to axonal regeneration. It is postulated that the astrocytic reaction is absent, regeneration of axons can occur. And it was reported that treatment with anti CD81 antibodies enhanced functional recovery in the rat with spinal cord injury. So in this current study, the author investigated the effect of the water extract of Persicae Semen on the regulation of GFAP and CD81 that increase when gliosis occurs. Persicae Semen decreased the expression of GFAP and CD81 in astrocyte cell by ELISA method. Persicae Semen decreased the RNA expression of CD81 and GFAP. The proteins that separate in whole cell were analaysed by western blot, and the expression of GFAP and CD81 was decreased. In vivo, rats brains were peformed cortical stab wound, the water extracts of Persicae Semen were injected for 7 days, 30 days. As a result, GFAP and CD81 expression were decreased in immunohistochemistry. These findings demonstrate that Persicae Semen decreases GFAP and CD81 expression. Accordingly, Persicae Semen could be a candidate for promotion of axon regeneration after CNS injury.