A radio-frequency package includes a radio-frequency device, a multilayer dielectric substrate, and an electromagnetic shield member. The multilayer dielectric substrate includes an internal conductor pad, a first signal via-hole connected to the internal conductor pad, an external conductor pad, a second signal via-hole connected to the external conductor pad, and an inner-layer signal line that connects between the first signal via-hole and the second signal via-hole. The internal conductor pad includes a leading-end open line having a length of substantially a quarter of a wavelength of a radio-frequency signal used in the radio-frequency device.