Background: Idiopathic pulmonary fibrosis (IPF) is a chronic disease that progresses over time and is characterized by scar tissue within the lungs in the absence of a particular triggering factor. IPF disease severity has traditionally been characterised using terms such as mild, moderate, or extreme. HRCT provides a correct diagnosis of IPF while preventing histological confirmation and interventional procedures. Objective: Purpose of the study is to elaborate different HRCT findings in patients with IPF and their correlation with oxygen saturation to determine disease severity. Materials and Methods: A descriptive cross-sectional study was conducted in a private sector hospital in Gujranwala named “Gondal Medical and Diagnostic Complex”. Total 80 patients were engaged in the study. HRCT was performed on Aquillion 64 slice CT scanner with 1.0 or 2.0 mm thick focal segments taken at 2 cm intervals from around the entire chest and then reconstructed. Results: In this study of 80 patients majority were male (62.5%), while the most common age associated with this disease was 41-50yrs (28.7%), the patients having asthmatic history was 30% and 25% had both smoking and asthma history, 47.5% patients having O2 saturation between 86-90% while the patients having both smoking and asthma history had shown GGO, RP along with honey combing and indicated disease severity by having worse rate of oxygen desaturation as compared to patients having only RP and GGO with better O2 saturation rate to some extent. So, honey combing with different CT features following asthma history in a patient were noted to have worse oxygen desaturation rate which was a brittle sign of disease severity. Conclusions: HRCT is a useful tool for estimating disease severity by correlating clinical histories and O2 desaturation rate with HRCT findings without histological verification and invasive procedures.