Abstract: Atrial fibrillation (AF) is one of the most common arrhythmia in clinic, with increasing prevalence in recent years. Atrial fibrosis is a crucial factor in the initiation and progression of atrial fibrillation, but the specific mechanism driving this change remains to be clarified. MicroRNA (miRNA) involves in the regulation of post-transcriptional gene expression, recent studies on tissue-specific miRNA have shown that it plays an important role in the atrial remodeling of AF. This article reviews the latest research advances in the association between miRNA and atrial fibrosis as well as its capacity in the treatment of AF.