Abstract: 　Objectives　To investigate the significance of electronic bronchoscopy and bronchoalveolar lavage in diagnosis and treatment in children with pulmonary mass lesion. Methods A total of 74 hospitalized children from January 2011 to June 2012 whose imaging examinations showed massive patchy shadow were examined and treated by electronic bronchoscopy and bronchoalveolar lavage. Their clinical data were retrospectively analyzed. Results The major cause for the massive shadow was infection according to electronic bronchoscopy examination (68/74, 91.89%), 65 cases of them were lobar pneumonia, 3 cases were pulmonary tuberculosis followed by 5 cases of foreign body (6.76%) and one case of pneumorrhagia (1.35%).The lower left lung was the most frequently seen site of infection, followed by lower right lung. The agreement between infection sites and imaging examination was 97.30%. Bronchoalveolar lavage fluid showed that the primary pathogen of lobar pneumonia infection is Mycoplasma pneumoniae (MP) (42/65, 64.62%). The highest detection rate of MP was found in preschool group and the detection rate between different age groups indicated statistically significant difference (P<0.01). The imaging examination showed pulmonary lesions in 61.54% children with lobar pneumonia improved significantly in one week. The improvement rate of pulmonary lesions was higher in infected children with short duration (1-2 weeks, 90.91%) between disease onset and electronic bronchoscopy inspection than those with longer duration (2-3 weeks, 51.72% and >3 weeks, 35.71%) (P<0.05). Conclusions Electronic bronchoscopy and bronchoalveolar lavage play dual roles in etiological diagnosis and therapy in children with pulmonary mass lesion.