Clean air is one of the basic necessities of life. Air has by volume 78.09% N₂, 20.9 % O₂, 0.93 Ar, 0.039% CO_2, small amount of other gases, impurities and solid contents in the form of particulate matter. Variation in the specific composition of air makes it unhealthy or in some cases lethal for the living organism.  Polluted air can cause many health problems in humans like respiratory allergy, asthma and other lungs diseases. Airborne particulates play very important role in polluting the air especially in urban areas. Particulates which are smaller in size like PM_2.5 do not settle easily and these particulates have the ability to stay buoyant and can be transferred to other region and concentration of Particulate Matter can be increased by that phenomenon. In Lahore city concentration of particulate matter is much higher than that recommended by NEQS.  According to field values, PM_2.5 concentration in Lahore remains two or threefold higher than National Ambient Air Quality Standard. Average annual PM_2.5 concentration in the city is 100-120 µg m^-3 while NEQS suggests that it should be less than 40 µg m^-3. The concentration of particulate matter remains maximum in months of November and December while it remains minimum in months of August and September. Vehicles are major source of fine particulates like PM₅ and PM_2.5, whereas Lahore city has very high vehicle flow having 4,175,430 vehicles on roads. As a result pollutants emitted from these vehicles are major source of pollution in the city. To evaluate the emission of particulate matter PM_2.5 from the vehicles at specific locations of the city and on overall city, Fixed Box and Modified Fixed Box Models were applied. Results show that concentration of PM_2.5 at Thoker Niaz Baig and Yateem khana Chowk is tremendously higher as there is very high vehicle flow at these locations, moreover it was found that PM_2.5 concentration remains minimum at Higher wind speed and maximum at lower wind speed. Models also provided the predictions of concentration of PM_2.5 in upcoming years when there will be much more vehicles in the city.