miRNA, regarded as an important negative gene regulator at the post-transcriptional level, plays a critical role in oligodendrocyte differentiation and pathogenesis of Alzheimer’s disease. Myelinating oligodendrocytes are important for the conduction of action potentials, synaptic plasticity and also for cognitive deficits of Alzheimer’s disease. Application of miRNA, especially oligodendrocyte-specific miRNAs in studying the pathogenesis of Alzheimer’s disease, will provide a new insight for the drug development and clinical diagnosis of the disease. In this paper we review the research progress in miRNA, oligodendrocytes and Alzheimer’s disease.