Abstract: miRNAs are small noncoding regulatory RNAs of 22 nucleotides in length that always become and pay close attention to the focus in the field of medicine and molecular biology. miRNAs play a role at posttranscriptional level by inhibiting sequence-specific translation or degrading mRNA via binding to target genes during the hyperplasia，differentiation and death of cell as well as hormone secretion. Recently，a link between miRNAs and development of the central nervous system，such as the differentiation of neural stem cells，synaptic connections，dendritic spinesor or neuroprotective effects，is becoming increasingly clear. Therefore，the central aim of this review is to highlight recent findings in the field of miRNAs inhippocampus，and a potential interaction between microRNAs and neurodegenerative diseases including cognitive impairment and Alzheimer′s disease，that provides newideas for future prevention and treatment of diseases.

Key words: MicroRNAs, Hippicampus, Cognition disorders, Nervous system diseases, Menopause