Galectin-3 belongs to a family of β-galactoside-binding proteins, which is characterized by highly conserved sequences in specific carbohydrate-recognition domains. A number of conventional risk factors for atrial fibrillation may be effective to promote the release of galectin-3 from macrophages,which in turn contributes to increasing accumulation of inflammatory cells in cardiac tissue and perpetuates their activation, promotes fibroblast activation and proliferation, thus leading to cardiac fibrosis, cardiac remodeling, myocardiocyte dysfunction and ultimately predisposing to atrial fibrillation.