To obtain a high relative permittivity prepreg containing a ceramic finer cloth base material which excels in heat resistance, electrical properties after moisture absorption, adhesion to a copper foil and the like.

The high relative permittivity prepreg is manufactured by allowing a resin composition comprising 80-99 wt.% insulating inorganic filler powder having a relative permittivity at room temperature of ≥500 to adhere to a ceramic fiber cloth having a relative permittivity of ≥50, perferably ≥500, and rendering the resulting cloth in the B-stage. Further, the high relative permittivity perpreg is manufactured with the use of a composition obtained by uniformly compounding a resin composition comprising (a) 100 pts.wt. polyfunctional cyanic acid ester compound and (b) 50-10,000 pts.wt. epoxy resin which is liquid at room temperature as the thermosetting resin and 0.005-10 pts.wt., based on a sum of components (a) and (b) of 100 pts.wt., thermosetting catalyst as the essential component with an insulating inorganic filler having a relative permittitity at room temperature of ≥500 and a specific surface area of 0.3-1.00 m2/g.