Upper gastrointestinal bleeding (UGIB) is one of the most common acute and critical diseases in internal medicine. With a considerable morbidity and mortality, it has become a global concern. This article summarized the related risk factors for UGIB. We found that age, gender, Helicobacter pylori (H. pylori) infection, chronic renal insufficiency, cardiac insufficiency with continuous-flow left ventricular assist devices, long-term use of non-steroid anti-inflammatory drugs (NSAIDs) and selective serotonin reuptake inhibitors (SSRIs) alone or in combination, meteorological factors, and unhealthy lifestyle such as smoking and alcohol consumption were risk factors of UGIB. Other possible factors like VKORC polymorphism need further studying. Clarifying risk factors of UGIB will definitely aid in optimizing its monitoring, improving therapeutic strategies, and effectively preventing recurrence, which eventually improves life quality and lowers financial burden.