Disclosed herein are a resin composition of a printed circuit board including a liquid crystal oligomer, an epoxy resin, and a phenolic curing agent having five or more functional groups, an insulating film and a prepreg manufactured using the resin composition, and a printed circuit board including the insulating film or the prepreg. The resin composition for a printed circuit board according to the present invention, and the insulating film and the prepreg manufactured using the same, may have low coefficient of thermal expansion, excellent heat resistance property, and a high glass transition temperature.