Chronic obstructive pulmonary disease (COPD) is a disease affecting the patient"es ability to perform normal daily physical and social activities, thereby affecting their quality of life (QoL). The aim of this study was to evaluate the effectiveness of education intervention carried out by clinical pharmacists on COPD patients’ QoL. A randomized, controlled trial was conducted at Department of Screening Respiratory Function, University Medical Center, Ho Chi Minh City, Vietnam from December 2017 to May 2018. Patients aged 40 years or older, who were diagnosed with COPD and agreed to participate were included in this study. Selected patients were randomized into two groups, the intervention group (IG) and the non-intervention group (NIG). The clinical pharmacist intervention program included education about COPD knowledge, medication usage, inhaler technique, the importance of medication adherence and smoking cessation, lifestyle adjustments, recognition and prevention of possible adverse drug effects. Participants were followed up by monthly telephone calls. Patients"e QoL was measured by the validated Vietnamese version of the Clinical COPD Questionnaire (CCQ). The main outcome was the difference in QoL scores between IG and NIG after the three-month follow-up. After three months, the number of patients in the IG and in the NIG was 73 and 68, respectively. The total CCQ score improved significantly after the pharmacist intervention (0.81 ± 0.54 in the IG vs. 1.24 ± 0.81 in the NIG, p < 0.001). Our study suggests that clinical pharmacist-led education can improve COPD patients’ QoL.