Haemophagocytic lymphohistiocytosis (HLH) is rare. Although Kawasaki disease (KD) has been reported as a precursor to HLH, coronary arteritis occurring at the onset of secondary HLH, not in association with KD, has not been reported. An 8-year-old girl presented with virus-induced secondary HLH associated with a giant aneurysm and ectasia of the coronary arteries which was detected incidentally at onset of the disease. She did not fulfill the criteria for diagnosis of KD. The coronary lesions improved after 6 months of treatment with dexamethasone and etoposide. Echocardiography early in the course of HLH is a useful tool to detect the unusual finding of coronary arteritis which may carry significant clinical sequelae.