A low-noise block downconverter (LNB) is disclosed. The low-noise block downconverter comprises a first input module, for outputting a first intermediate frequency (IF) signal after receiving a first polarization signal via a first input end; a second input module, for outputting a second IF signal after receiving a second polarization signal via a second input end; a first output module, coupled to the first input module, for amplifying the first IF signal, to output a first user signal to a first user; and a second output module, coupled to the second input module, for amplifying the second IF signal, to output a second user signal to a second user.