Background: Extra-articular findings common in patients with rheumatoid arthritis. Lung disease is the second most common cause of death in patients with rheumatoid arthritis after infection. Patients with rheumatoid arthritis have a great lack of knowledge and awareness about rheumatoid lung disease. Aim: To compare pulmonary function tests in patients with asymptomatic rheumatoid lung disease and pulmonary function tests in healthy subjects. Study Design: A cross-sectional analytical study. Location and duration of the study: In the Medicine Unit II of Jinnah Hospital Lahore for one year duration from March 2019 to March 2020. Methods: Pulmonary function test of 60 rheumatoid arthritis and 60 age, sex and BMI matched healthy individuals, having no pulmonary signs, symptoms or disease were compared. The data obtained was analyzed by using SPSS version 18.0. Results: FEV1in RA [84.50 (77.0-92%)] was significantly lower than in healthy subjects (p = <0.0001) [96.0 (96.0-97%)]. The FVC percentage [85.0 (77.0–93.50)] was significantly lower in RA patients than in healthy subjects (p = <0.0001) [98.0 (96.25-99%)]. There was a significant difference in the FEV1: FVC ratio [85.15 (78.6-88.5)] in RA patients and healthy people (p = 0.020) [84.0 (83.0-88.95)]. Conclusion: Spirometry (lung function test) is a cost-effective test for detecting an early decline in lung function in patients with asymptomatic rheumatoid lung disease. Key words: rheumatoid arthritis, rheumatoid lung disease, lung function test.