Partial bronchiectasis of the lower lobe of the left lung with infection is serious and requires immediate treatment with anti-infection and sputum drainage, but is usually not serious enough to be life-threatening. 1. Presenting with partial bronchiectasis of the lower lobe of the left lung, the main manifestations are cough, sputum and chest tightness. According to the drug sensitivity test to select sensitive antibacterial drug treatment, oral aminobromine, acetylcysteine effervescent tablets sputum or nebulized acetylcysteine solution, terbutaline, such as sputum diastolic bronchial chest tightness to improve the promotion of sputum drainage, coughing up sputum difficulty, or sputum thrombosis, but also to carry out the bronchoscopy of alveolar lavage treatment. 2. If part of the lower lobe of the left lung has bronchiectasis and the infection is not well controlled, leading to recurrent infections in the same area, there is a risk of aggravation of the condition causing respiratory failure, diffuse bronchiectasis, and life-threatening risk of severe infections. In conclusion, when bronchiectasis with infection occurs, it is necessary to consult a doctor in time and treat the cause under the guidance of a specialist.