Objective To analyze the effect of adaptive ventilation mode ventilation on respiratory, blood gas and inflammatory response in COPD patients with type Ⅱ respiratory failure. Methods 90 COPD patients with type Ⅱ respiratory failure who were treated in our hospital from January 2015 to December 2016 were selected as the subjects.The patients were divided into observation group and control group according to the random number table method, 45 cases in each group.The patients in the observation group were treated with adaptive ventilation mode, and the control group was treated with synchronous and intermittent arterial ventilation combined with pressure-supported ventilation mode for mechanical ventilation.The use of ventilator, respiratory parameters, blood gas and inflammatory response were observed in both two groups. Results The respiration rate and ventilation time[(14.21±0.72)times/min, (13.97±3.61)d]in the observation group were lower than those in the control group[(16.85±0.94)times/min, (16.24±3.96)d], the tidal volume[(612.58±49.47)mL]in the observation group was higher than that in the control group[(526.35±30.29)mL], the differences were statistically significant(t=14.956 7, 2.841 8, 9.972 1, all P 0.05). The levels of CRP, α1-AGP, PCT, IL-6 and TNF-α in the observation group were (90.71±29.68)mg/L, (1.26±0.52)g/L, (2.27±1.03)pg/L, (115.79±24.54)mg/L, (45.65±4.39)mg/L, which were lower than those in the control group[(123.54±40.62) mg/L, (3.73±1.12)g/L, (6.49±1.36)pg/L, (127.43±28.91)mg/L, (53.78±5.65)mg/L], the differences were statistically significant(t=4.377 6, 13.418 3, 16.593 4, 2.059 1, 7.622 3, all P<0.05). Conclusion Adoptive ventilation mode can improve the ventilation status of COPD patients with type Ⅱ respiratory failure, promote the recovery of spontaneous respiration, reduce the ventilation time and reduce the inflammatory response.It is suggested to be widely used in clinical practice. Key words: Mechanical ventilation; Pulmonary disease, chronic obstructive; Type Ⅱ respiratory failure; Inflammation