In order to support as critical input to air quality forecasting task during Commonwealth Games (CWG) – 2010 in mega city Delhi, we have developed a high resolution emission inventory of major atmospheric pollutants. For the same, inventories of ozone precursors like NOx and CO are developed over a domain of 70 km × 65 km with a grid of 1.67 km ×1.67 km resolution covering Delhi and surrounding region using Geographical Information System (GIS) technique for base year 2010.