Objective To establish a rat model of chronic obstructive pulmonary disease (COPD) with phlegmdampness syndrome. The metabolic characteristics of this rat model were revealed using metabolomics technology. Methods A rat model of COPD with phlegm-dampness syndrome was established by forced smoking combined with LPS airway infusion, forced swimming, and alternate-day fasting. The rat model was evaluated by observing behavioral changes; measuring the body weight, anal temperature, blood indexes, and IL-6, IL-1β, and TNF-α contents; and observing tissues histopathological changes. Differential plasma metabolites between the normal group and the model group were detected and screened by liquid chromatography-mass spectrometry, and enrichment analysis was conducted for metabolic pathways. Results Compared with the normal group, COPD rats with phlegm-dampness syndrome showed different severities of symptoms, including coughing, wheezing, depression, fatigue, withered and dry hair color, weight loss, increased water intake, increased body temperature, production of loose feces containing fat, and a white and smooth tongue coating. In the model rat, the number of white blood cells and lymphocytes in the peripheral blood and the contents of IL-6, IL-1β, and TNF-α in the BALF significantly increased. In the lung tissue, there was obvious inflammatory cell infiltration; the alveolar lumens appeared as different sizes; and the mucous membranes of the colon, duodenum, and ileum were partially exfoliated. There were 116 metabolites that differed between the normal group and COPD group with phlegm-dampness syndrome. These metabolites mainly involved metabolic pathways, including amino acid biosynthesis and metabolism; vitamin digestion, absorption, and metabolism; lipid and lipoid biosynthesis and metabolism; and other metabolic pathways. Conclusions This study provides an effective method for establishing a rat model of COPD with phlegmdampness syndrome and a corresponding evaluation system and has preliminarily revealed the main metabolic characteristics of this rat model.