To provide a high dielectric constant B-staged resin sheet and a printed wiring board using the same.

The high dielectric constant B-staged resin composition sheet can be obtained by using a resin composition obtained by incorporating 80-99 wt.% insulating inorganic filler having a dielectric constant at room temperature of ≥500 into an epoxy resin composition comprising (a) an epoxy resin which is liquid at room temperature and (b) a thermosetting catalyst as the essential components, 1-75 wt.% insulating inorganic filler used being a needle insulating inorganic filler, and the printed wiring board uses the resin composition sheet. Thus, a high dielectric constant resin sheet could be manufactured, and a high dielectric constant printed wiring board using this sheet and having excellent heat resistance, electrical properties after moisture absorption, adhesion to copper foils, strength, and the like, could be manufactured.