The physicochemical properties of the middle distillates of exhaustive refining of crude oil at one of the Russian refineries are studied from the standpoint of their utilization as components of low-viscosity marine fuels. The performance properties of diesel fractions after hydrofining and of light gas oils of catalytic cracking and delayed carbonization are determined and compared. The physicochemical and performance properties of the studied fractions are found to depend on the hydrocarbon composition of the fractions. Based on the noted dependences, the optimum component composition of low-viscosity marine fuel is developed and recommended for introduction.