Rheumatoid arthritis (R.A.) is characterized by chronic inflammatory symmetrical peripheral polyarthritis associated with systemic involvement. Pulmonary involvement is one of them. Therefore, early assessment of pulmonary function may help identify the type of respiratory involvement and hence can contribute to properly managing pulmonary complications.The study aims to evaluate the type and extent of pulmonary function abnormality in relation to the duration of Rheumatoid Arthritis. Settings and Design: tertiary care treating hospital- a cross-sectional observational study A cross-sectional study was conducted at Department of General Medicine in forty R.A. cases in whom spirometry was performed and values of spirometry results were statistically compared with the duration of R.A. using S.P.S.S. software. Cases were grouped into three categories based on the duration of the disease. Category A –less than 5 yrs, category B– 5 to 9 yrs and category C – more than 9 yrs duration. In category A, abnormal pulmonary function test (PFT) was observed in 43.5% of cases in the form of obstructive 17.4%, restrictive 17.4% and mixed pattern in 8.7% of cases. In category B, the restrictive pattern was found in 63.6% and a mixed pattern in 9.1% of cases. However, abnormal pulmonary function test (PFT) was observed in all cases in category C, with obstructive pattern in 16.7%, restrictive 66.7% and mixed 16.7% cases. From the study, it was found that early pulmonary involvement occurs in R.A. With an increase in the duration of R.A., pulmonary involvement becomes a more severe and restrictive pattern. Most cases with a duration of more than 9yrs had significant pulmonary involvement either in the form of restrictive or obstructive pattern. Hence PFT should be done at the earliest as a routine and repeated periodically in R.A. cases.