Abstract: The invention is directed to a piston skirt oil seal system comprising a piston with a skirt operating in a cylinder chamber between an oil sump and a combustion chamber in an internal combustion engine. A first retainer attaches to the piston skirt, and a second retainer attaches to a cylinder wall defining the cylinder chamber above the oil sump. A boot made of a flexible, impervious membrane extends between the first and second retainers. The boot serves as a barrier preventing the migration of oil from the oil sump into the combustion chamber reducing the amount of unburned hydrocarbons introduced to the catalyst. To overcome gas leakage and friction, at least one self-lubricating or gas lubricated ring attaches to the piston above the boot. In an alternative embodiment, the boot forms an oil migration barrier through the use of a series of concentric rings linked together in a telescoping arrangement.