Chromatin remodelling, including histone modifications has been recognized to play a central role in the regulation of gene expression. Histone modifications are mostly based on studies in cell culture systems in vitro. Recent evidence suggests that histone modifications are actively involved in activity-dependent neural plasticity via regulation of critical gene transcription necessary for the biological process in vivo. We have reviewed here the recent works studied on long-term memory formation, visual cortical plasticity during the critical period and drug-induced status epilepticus to elucidate a role for histone modifications in these biological processes. All of the studies indicate that chromatin structure, including histone modifications is highly dynamic within the nervous system and suggest the possibility that chromatin structure itself might be recruited as a target of plasticity-associated signal transduction mechanisms.