Crude oil is a naturally occurring, unrefined petroleum product composed of hydrocarbon deposits and other organic materials. I separated a crude oil sample into different fractions using the SARA fractionation method. I then used a ESI Q-TOF mass spectrometer to analyse the aromatic fractions gotten from the SARA fractionation. The raw data obtained from the mass spectrometer was exported into the excel program and sorted based on elemental composition and the m/z, intensities, carbon number,DBE etc. were determined. These parameters are then used to create diagrams, which provides more information on how to study the characteristics of the aromatic compound.