Abstract: Autosomal dominant polycystic kidney disease (ADPKD) is a multisystem inherited disorder in which cardiovascular complications are common. This paper reports a case of ADPKD caused by a polycystin-1 (PKD1) gene mutation, presenting predominantly with mitral valve prolapse and severe mitral regurgitation. The patient had a history of hypertension, arrhythmia, polycystic liver disease, and cerebrovascular malformations, with a positive family history of cerebrovascular events. Genetic testing identified a C＞T mutation in exon 19 of the PKD1 gene. The patient underwent mechanical mitral valve replacement and radiofrequency ablation, with good postoperative recovery. This case suggests that ADPKD may present with significant valvular heart involvement, and that early evaluation of cardiac structure and function is warranted in ADPKD patients with hypertension or cardiac murmurs to facilitate timely identification and management of cardiovascular complications.