Atrial fibrillation (AF), a common supraventricular arrhythmia, is associated with severe complications, including ischemic stroke and heart failure, significantly increasing morbidity and mortality rates. Its pathogenesis encompasses a wide array of electrophysiological and pathophysiological mechanisms. Central to AF"s onset, persistence, and recurrence is atrial structural remodeling, notably characterized by left atrial (LA) myocardial fibrosis, which acts as a crucial predictive indicator. Catheter ablation (CA) is the preferred treatment for symptomatic or drug-resistant AF, despite a notable recurrence rate post-procedure. Contemporary research highlights a significant link between LA fibrosis and AF recurrence following CA. Thus, precise evaluation and quantification of LA fibrosis are imperative for identifying AF patients at high risk, formulating individualized ablation approaches, and estimating the likelihood of post-CA AF recurrence. This paper thoroughly reviews the interconnected mechanisms between LA fibrosis and AF, encompassing aspects such as imaging and serological evaluations, with the aim of informing AF prevention and management strategies.