Abstract: Left atrial appendage closure (LAAC) has become an important alternative for patients with nonvalvular atrial fibrillation who had contraindication to oral anticoagulants or cannot tolerate oral anticoagulant therapy for a long time. Although LAAC has been widely used, there are some complications that need to be solved perioperatively or after LAAC. Watchman 2.5^TM and Amplatzer Amulet are the two most commonly used devices for LAAC. The application of the existing devices is limited for the treatment of some complex lesions due to the structure of the devices. Watchman FLX is a new-generation device for LAAC and Watchman FLX had excellent procedural success rates, high LAA seal rates and low rates of thromboembolic events. This article reviews the latest researches on Watchman FLX.