Mucormycosis is a life threatening condition caused by invasion of fungi of the order Mucorales. Gastrointestinal invasion is very rare and often lethal, particularly in disseminated mucormycosis. We present the case of a 26-year-old woman from North Africa with type 2 diabetes who, after a cholecystectomy, developed unexplained septic shock and haematemesis due to gastric necrosis. Computed tomography (CT) revealed a disseminated fungal invasion of the lungs, kidney and paranasal sinuses. A gastrectomy and subsequent amphotericin B treatment resolved her condition. The number of patients with mucormycosis is increasing. Early diagnosis of high risk patients with CT and biopsies from which fungi are directly isolated must be followed by surgery and systemic amphotericin B infusion.