Background: Air pollution in India is a serious issue with the major sources being motor vehicle emissions, thermal power stations, cooling towers, biomass burning, fuel adulteration, factory smoke, and stubble burning. Chronic exposure to ambient air pollution has obtunded effects on the development of lung function in children and detrimental effects on lung function of adults. The adverse effects of pollution on lung function increase the development of lung diseases in the future. Aims and Objective: The aim of the study was a comparison of lung function between two groups of population with different occupations, one group with outdoor occupation (high exposure) and second group with indoor occupation (low exposure). Settings and Design: It was a cross-sectional study and the sampling approach was Quota sampling. Quota sampling is a type of non-probabilistic sampling. There are certain groups of people who are particularly vulnerable to ambient air pollution because of their sustained high exposure like traffic police personnel deputed at traffic junctions, auto rickshaw driver/Taxi driver, E-Rickshaw driver plying in this area, and road side vendors this group. Low exposure group chosen were employee of offices and showrooms who are working indoor. Methods and Materials: This study was a two groups of 245 participants in each. First group with outdoor occupation and second group with indoor occupation having different level of exposure to air pollution due to their nature of occupation. Lung function parameters FEV1, FVC, FEV1/FVC, PEFR, and FEF were compared between two groups. Statistical Analysis: SPSS 26 software was used. Independent “T” test for continuous data type for different population, paired “T” test within the group, and Chi-square test for categorical data were applied. Results: Among high exposure group, 62.7% and 9.4% were found to have restrictive and normal lung function pattern, respectively. In comparison, among low exposure group, 31% and 59.5% were found to have restrictive and normal lung function pattern, respectively. Among outdoor group, there was a significant decline of lung function parameters such as FEV1, FVC, FEV1/FVC, PEFR, and FEF in comparison to indoor group. Conclusion: In this study, the lung function parameters were decreased in population working outdoor and chronically exposed to air pollution, in comparison to indoor subjects.