A base station antenna and a base station including the base station antenna are provided. A base station antenna includes a transceiver array configured to output M signals, wherein M is an integer greater than 1; an antenna array including N antenna units, wherein N is an integer greater than M; a first-level signal allocating network configured to allocate first power to the M signals, and output P signals, wherein P is an integer greater than M; a signal synthesizing network including multiple signal synthesizers, wherein each of the multiple signal synthesizers utilizes two signals of the P signals to synthesize two output signals; and a second-level signal allocating network configured to allocate second power to signals output by the multiple signal synthesizers, and output N signals to the N antenna units.