Abstract: Atrial fibrillation (AF) is one of the most common arrhythmias. A better understanding of the risk factors of non-valvular AF is helpful to improve clinical prognosis, as well as life quality of patients. Non-valvular AF occurs in the young and older populations. Modifiable non-valvular AF risk factors, including race, gender and age, and unmodifiable AF risk factors, including smoking, alcohol abuse, intake of energy drinks, obesity, intense exercise, obstructive sleep apnea syndrome (OSAS), hypertrophic cardiomyopathy (HCM), congenital heart disease (CHD) and traumatic intracranial hemorrhage (TICH) for young people are summarized in this review. For a better primary and secondary prevention for non-valvular AF focused in the young, this article focuses on analysis of epidemiology and pathogenesis of all controllable factors.