The present invention provides a metal clad laminate or a resin coated metal foil having a metal foil whose both surfaces are not substantially roughening-treated and an insulating resin composition layer using generally used insulating resin, and a printed wiring board and a manufacturing method thereof, in which the metal clad laminate or the resin coated metal foil is used, the reliability and circuit formability are high, and the conductor loss is extremely low.