Eosinophilic gastrointestinal diseases (EGIDs) are a group of chronic conditions, characterized by an excessive accumulation of eosinophils in various areas of the mucosal of the gastrointestinal (GI) tract. EGIDs encompass a spectrum of diseases, including eosinophilic esophagitis (EoE), eosinophilic gastritis (EoG), eosinophilic enteritis (EoN), and eosinophilic colitis (EoC), each affecting different segments of the GI tract. The pathogenesis of EGIDs is multifaceted and involves an intricate interplay between genetic predisposition, environmental triggers, and dysregulated immune responses. Although the exact etiology behind EGIDs is not fully understood, it is clear that they are immune-mediated, with eosinophils having a central role in inflammation and tissue damage of GI mucosal. Clinical manifestations depend on the organ that is affected by the disease and on the depth of the eosinophil infiltration of the bowel wall. They range from mild discomfort to severe dysphagia, abdominal pain, malnutrition, and growth failure, particularly in pediatric cases. Regarding EGID management, it is a challenging issue to achieve clinical and histologic remission using pharmacotherapy and dietary elimination. Corticosteroids and proton pump inhibitors can be selected as an effective first-line treatment for certain patients and six-food elimination diet (6-FED) has been proven effective in inducing remission. Furthermore, biologic therapies have emerged as essential tools in controlling eosinophilic-driven inflammation. This review focuses on the complex pathogenesis and treatment of these inflammatory diseases, especially EoE.