This study aimed to estimate the incidence and risk factors of device-related thrombus (DRT) following percutaneous left atrial appendage closure (LAAC) in real-world practices. Between February 2012 and December 2016, 319 consecutive patients with atrial fibrillation underwent percutaneous LAAC using WATCHMAN, WATCHMAN Flx, Amplatzer cardiac plug, and Amulet devices. All patients underwent transesophageal echocardiography (TEE) at a minimum of three time points; periprocedurally, at 45 days, and at 6 months. Other clinical parameters were also evaluated, and a comparison between patients with DRT and those not suffering from DRT was done. The percutaneous LAAC was successfully performed in 97.8% of the patients. DRT was detected in 14 (4.49%) patients; of the 14 patients, DRT was detected in 3 patients at acute phase, 8 patients at subacute phase, 2 patients at late phase and 1 patient at very late phase. Most of the DRT originated from the central screw of device. In 6 out of 14 patients, DRT was successfully resolved by oral anticoagulation. Higher HAS-BLED score (4.1 ± 1.2 vs. 3.5 ± 1.1, p = 0.042) was more frequent in patients with DRT. Multivariable analysis showed that residual peri-device leak may result in a predisposition to DRT (p = 0.023). The incidence of DRT after percutaneous LAAC was acceptable, as a part of the DRT was resolved with oral anticoagulation. Residual peri-device leak was associated with DRT. Optimal implantation without peri-device gap, individual antithrombotic regimens, and careful monitoring with TEE follow-up could be conducive to the prevention of DRT.