 This study is a local, prospective, open-label, company-sponsored, non interventional, multi-center study. Patients documented must suffer from an acute exacerbation of chronic bronchitis and take at least one dose of Moxifloxacin injection.The primary objective is to obtain clinical effectiveness and safety data of Moxifloxacin injection in the treatment of acute exacerbations of chronic bronchitis in patients in whom Moxifloxacin was routinely prescribed. The secondary objective is to find out the possible correlation between the risk factors sex, smoking, number of previous exacerbations, etc and AECB, the different treatment effectiveness according to Anthonisen classification. This study will also collect the data of pathogens by sputum culture and the defervescence time of Moxifloxacin injection in treating Acute Exacerbations of Chronic Bronchitis AECB. 