The objective of this study was to determine whether pharmaceutical care by pharmacists could improve medication adherence and quality of life in patients with chronic obstructive pulmonary disease or not. A prospective interventional study was conducted among 156 patients to assess medication adherence and find the reason for non-adherence, analyze the quality of life, and provide counseling to improve the quality of life in patients, to determine whether pharmaceutical care by pharmacists could improve medication adherence as well as the quality of life and to prepare patient information leaflet to educate the patients regarding the disease. Prescriptions were collected and Medication Adherence Questionnaire and St. George’s Respiratory Questionnaire were used to assess medication adherence and quality of life respectively. Among 156 patients, 76 were taken as a control group and the other 80 were taken as an intervention group. At the baseline, the patients in both intervention and control groups were found to have no significant difference. After the second follow-up, the total quality of life score was improved significantly in the intervention group when compared with the control group (53.55 ± 6.79 vs.68.89 ± 9.13, p=0.001).  Medication adherence was significantly improved after pharmacist intervention (6.38 ± 1.53, 7.42 ± 0.74, p=0.001)  as compared with control group(4.73 ± 2.16, 4.89 ± 2.18, p=0.01). As per the study results, the implementation of pharmacist intervention played an important role in improving medication adherence as well as the quality of life of chronic obstructive pulmonary disease patients. It may improve patient outcomes and reduce their social and economic burdens. Keywords: Pharmacist intervention, Medication adherence, COPD, MAQ, SGRQ.