Bronchitis is categorized into acute bronchitis and chronic bronchitis. Laboratory tests mainly include blood tests, sputum culture tests, X-ray chest radiographs and pulmonary ventilation function tests. 1. Acute bronchitis (1) Blood test: Some acute bronchitis is related to viral infection, and the blood test usually has normal white blood cells or is accompanied by elevated lymphocyte ratio. Some acute bronchitis is caused by bacterial infection, in this case, the laboratory test will show that the total number of white blood cells and the percentage of neutrophils are elevated, and if the blood sedimentation test is carried out, it will be found that the blood sedimentation is accelerated. (2) Sputum culture: Acute bronchitis is usually treated with empirical antibiotic drugs without the need for sputum culture tests. 2. Chronic bronchitis (1) Blood test: The blood test of chronic bronchitis usually has no obvious abnormality. If it is in the acute exacerbation period, the total number of white blood cells and neutrophil count will be increased. (2) Sputum culture: Gram-positive and Gram-negative bacteria or a large number of destroyed leukocytes and cup cells can be found. Sensitive antibiotic drugs should be selected according to the cultured causative bacteria. The above diseases should be diagnosed comprehensively with clinical symptoms and other test results, and it is important to communicate with your doctor in time and view under your doctor’s guidance.