Volatile oil price and environmental impact of conventional jet fuel are key motivators towards the proposing of alternative jet fuels. This article introduces and establishes a relationship between jet fuel properties/composition and smoke emission. It is an important and comprehensive task as it underlines the base references and scientific reasoning on fuel compositions / properties; very few, if any, studies have investigated the effects of each of the properties/ compositions on smoke emissions. Two sets of fuels were tested on small re-commissioned Honeywell GTCP85 APU gas turbine Engine. The first set was consisted of 8 novel fuels, while the second was a blend of varied percentages of Jet A-1 and other alternative fuel. This is to provide a wide range of properties and compositions. The results were compared to those of Jet A-1on the same platform (Honeywell GTCP85 APU). It was observed that not all fuel compositions/properties have the same effects on the smoke number. Some of them such as: Specific Energy, Kinematic, viscosity, Biphenyls, monocycloparaffin, AlkylBenzene, Fluorenes, Distillation temp (90%), Carbon (%mass), Naphthalene, Composite Density, Benzocycloparaffin, Density at 15C°, Aromatics (%Vol) and Net heat of Combustion have a clear direct effect on the smoke number, while others such as iso-paraffin and flashpoint have a reduced impact on smoke number. This data shall be used to predict the effect of certain composition/ property on the smoke emission, thus it could be avoided or to be taking into considerations when producing or using new alternative fuels.