Abstract: Objective To investigate the correlation of serum leptin and to energy consumption and metabolization in the patients with chronic obstructive pulmonary disease (COPD). Methods We included 92 outpatients with stable COPD in West China Hospital of Sichuan University as trail group (COPD group) and 80 healthy elderly people in community as control group. All patients and healthy control received the measurements of body mass index (BMI), fat mass, resting energy expenditure （REE）, lung function, serum leptin and tumor necrosis factor-α （TNF-α）. Results The concentrations of serum leptin, BMI and lung function were lower in COPD group than those in control group （P<0.01）.The concentrations of serum leptin between two groups were not difference after the adjusted results of BMI and fat mass. There was no difference of REE and TNF-α concentrations in these two groups. The serum leptin had positive correlation with BMI and fat mass， but there were no correlation between of TNF-α and serum leptin. Conclusion In elderly people with stable COPD, the decline on the serum leptin is related to the decrease of BMI and fat mass, but barely related to the level of TNF-α.