To achieve effective remediation of subsurface petroleum hydrocarbon contamination, definite scientific and technical knowledge of their fate after they are spilled onto the ground surface or leaked from underground storage tanks is essential. The paper provides extensive details of the parameters that affect the fate of petroleum products in the underground environment. These include: the character of the subsurface environment; the composition, physical and chemical properties of petroleum products; and the mechanisms of their mobilization, immobilization and transformation in the subsurface. Data on the physical and chemical properties of soil, groundwater and petroleum hydrocarbons are identified. The mechanisms that affect the fate of these contaminants in the subsurface include vaporization and condensation, diffusion, advection, dispersion, dissolution, adsorption, biodegradation, and abiotic reactions. The relation between these mechanisms and the properties of soil, groundwater and petroleum hydrocarbons is described. The distribution of the contaminated petroleum products in the subsurface as affected by these parameters and principles is also described.