Disclosed is a wideband and multi-band frequency up converter used in a satellite earth station. The converter includes a first mixer configured to mix an intermediate frequency (IF) signal and a first local signal, and generate an IF′ signal; a narrow band filter configured to filter the IF signal; a first local oscillator configured to generate a first local signal so that the IF′ signal passes the narrow band filter; a second local oscillator configured to generate a second local signal needed to convert the IF′ signal into a desired frequency (RF) band; a second mixer configured to mix the IF′ signal filtered in the narrow band filter and the second local signal, and generate an RF signal; a wideband filter configured to filter the generated RF signal; and a control unit configured to vary a frequency of the first local signal.