Background: Although bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) remains problematic, especially in patients taking anticoagulants, there are differing views on the ideal and optimal management for these patients. This study investigated the risk of bleeding after ESD in patients taking anticoagulants. Methods: We enrolled 61 consecutive patients taking anticoagulants (anticoagulant group) and 968 patients taking no antithrombotic agents (non-antithrombotic group) treated with ESD for EGC between December 2010 and October 2016. We analyzed the risk factors for bleeding after ESD in relation to the various clinical factors. Results: Incidences of bleeding after ESD were significantly higher (14%; 11/76) in the anticoagulant group compared to the non-antithrombotic group (3%; 40/1,167). Moreover, bleeding after ESD was significantly more common in patients in the warfarin monotherapy group (14%; 5/37) and in the direct oral anticoagulant (DOAC) monotherapy group (22%; 4/18), compared to the non-antithrombotic group. Multivariate analysis revealed that dialysis, the use of anticoagulants, and an operation time ≥75 min were independent risk factors for bleeding after ESD. Conclusions: Our data suggest that patients who take warfarin and receive heparin bridging, and those who take DOAC medication, are prone to bleeding after ESD for EGC.