Objective: To analyze the effect of the adjuvant therapy with bronchoalveolar lavage, pulmonary surfactant protein,lactate dehydrogenase (LDH), penetrating hormone 3 (PTX3) level, and arterial blood gas indexes in children with refractory mycoplasma pneumonia (RMPP). Methods: Clinical data of 97 children with RMPP in our hospital from October 2016 to June 2022 were collected retrospectively, and divided into the drug treatment group (48 cases) and bronchoalveolar lavage group (49 cases) according to the different treatment methods. The children in the drug treatment group were treated with macrolide for anti-infection and symptomatic treatment. The children in the bronchoalveolar lavage group were treated with bronchoscopic bronchoalveolar lavage on the basis of the drug treatment group. The curative effect, the levels of pulmonary surfactant protein A (SP-A), pulmonary surfactant protein D (SP-D), LDH and PTX3 and arterial blood gas indexes before and after treatment of the two groups were compared. Results: The total effective rate in the bronchoalveolar lavage group was 89.80 %, which was obviously higher than that in the drug treatment group (70.83 %) (P＜0.05). Before treatment, the levels of SP-A, SP-D, LDH, PTX3 and arterial blood gas indexes had no significant difference between the two groups (P＞0.05). After treatment, the levels of SP-A, SP-D, LDH and PTX3 in the bronchoalveolar lavage group were obviously lower than those in the drug treatment group, and the arterial blood gas indexes were obviously better than those in the drug treatment group (P＜0.05). The incidence of adverse reactions in the bronchoalveolar lavage group (10.00 %) was obviously lower than the drug treatment group (26.00 %) (P＜0.05). Conclusion: The adjuvant therapy with bronchoalveolar lavage in the treatment children with RMPP has a good treatment effect, which could significantly improve the arterial blood gas indexes and lower the levels of pulmonary surfactant protein (SP-A, SP-D), LDH and PTX3 with high safety.