The present application relates to the field of communication antenna, and provides a common aperture radiation unit and antenna. The common aperture radiation unit includes a base, a first frequency band unit, and a second frequency band unit. The first frequency band unit includes a low frequency radiator and a first feeder group, the low frequency radiator is supported on the base, the low frequency radiator includes at least one polarization, and the first feeder group includes at least one first feeder member, which is used to coupling feed the low frequency radiator. The second frequency band unit is embedded in the first frequency band unit, the second frequency band unit includes a high frequency radiator and a second feeder group. The high frequency radiator is supported on the base, the high frequency radiator includes at least one polarization, and the second feeder group includes at least one second feeder member used to coupling feed the high frequency radiator.