A multiplexer with a common port feeding structure is disclosed. The multiplexer with a common port feeding structure of the present invention comprises: a housing comprising an antenna connector connected to an antenna for bidirectional transmitting and receiving and a plurality of input/output connectors bidirectionally inputting and outputting a specific frequency band of wireless signals which are input/output through the antenna; a plurality of band-pass filter units mounted inside the housing to transmit wireless signals at between the antenna connector and the input/output connector to pass a specific frequency band; and a coupling unit having a plurality of feeding members to couple the antenna connector and each of the plurality of band-pass filter units.