Venous thromboembolism (VTE) is a serious extraintestinal complication of inflammatory bowel disease (IBD). Patients with IBD have a VTE risk 3 times greater than those without IBD. IBD children are exposed to that risk as well but with lower incidence compared to adults, 9 events per 10,000 patients per years in children. The acute IBD flare is a predisposing factor to VTE. The management of thromboembolism in IBD patients includes treatment of a thromboembolic complication and secondary prophylaxis of the recurrence of a thromboembolic event. The paper reports a case of a boy with ulcerative colitis who developed cerebrovascular VTE during IBD flare.