Objective To improve the clinicians" levels of respiratory management and treatment of children with spinal muscular atrophy (SMA) with pulmonary infection. Methods A retrospective analysis of the clinical data of 49 children with SMA complicated with pulmonary infection admitted from January 1, 2013 to July 31, 2020. Results Among the 49 cases, 35 cases were type I, 14 cases were type II, and there was no type III patient. Compared with type II, SMAI children with lung infection had an earlier age of onset, a longer average hospital stays (P<0.05). The rate of cardiac insufficiency and respiratory failure in children with SMAI type was significantly higher than that of patients with SMAII type (P<0.05). The cough rate of SMAII type was significantly higher than that of SMAI type patients (P<0.05). The detection of respiratory pathogens of the SMAI type is mainly multi-drug resistant bacteria and conditional pathogens, and the SMAII type is mainly infected by Mycoplasma and Streptococcus pneumoniae. The rate of invasive ventilation and the use of carbapenem antibiotics in children with SMAI werec significantly higher than those in the SMAII group (P＜0.05). Conclusion Children with SMA are prone to pulmonary infection. Actively promoting the discharge of airway secretions, appropriate respiratory support and reasonable anti-infection are the key to the treatment of SMA complicated with lung infection.