Abstract: A resonator type silencer installed in an intake system of an automotive internal combustion engine. The resonator type silencer comprises a generally cup-shaped base member integrally connected with an air duct through which intake air to be inducted into the engine passes. The air duct is formed with an opening through which the inside of the base member is in communication with the inside of the air duct. The base member is formed at its opened end with a peripheral flange. A cover member is formed at its opened end with a peripheral flange which is bonded to the peripheral flange of the base member to define a sealed chamber. A partition plate is fixedly disposed inside the sealed chamber to divide the sealed chamber into a first resonance chamber defined by the base member, and a second resonance chamber defined by the cover member.