Nocardia spp is a gram-positive aerobic filamentous bacteria that causes pulmonary and systemic infections, especially in patients with immunosuppression or chronic lung diseases. It is rarely reported in children with cystic fibrosis. Macrophage activation syndrome is a life-threatening disease with an excessive inflammatory response usually triggered by infections. There are few reports in cystic fibrosis related to macrophage activation syndrome. Herein we report a child with cystic fibrosis who had macrophage activation syndrome due to Nocardia infection.