Objectives: To compare the role of low dose Theophylline and Tiotropium rotacap in improving the lung functions and day to day life of patients suffering from COPD. Study Design and Setting: A Clinical trial study was conducted at Department of Pharmacology and Therapeutics, BMSI in association with Department of Chest Medicine, JPMC. Methodology: This study was planned as an open label and parallel clinical trial study. A total of 168 patients of COPD were selected for this study and only 161 patients completed the 3 months duration of the study. The enrolled patients were grouped into 2, namely A and B. Tab. Theophylline 350 mg was given to Group A in two divided doses while Tiotropium rotacap18µg through rotahaler was given to group B once a day. Results: Mean FEV1 ± SD was improved by 0.04 ± 0.02 in Theophylline therapy group while by 0.07 ± 0.01 in the Tiotropium therapy treated group and a significant difference between the changes in the two treatment groups was evident. There was a percentage improvement in PEFR of 8.9 ± 5.8 in the Theophylline therapy treated group and of 13.2 ± 4.7 in Tiotropium therapy treated group. When Tiotropium group was compared with Theophylline group for improvement in percentage change in PEFR from day 0, a significant difference was evident between the two groups. There was a significant improvement from day 0 in CAT score in Tiotropium treated groups versus Theophylline group after 3 months of therapy. Conclusion: Tiotropium rotacap was more effective as compared to low dose Theophylline in improving pulmonary functions and CAT score in patients with COPD