The double-balanced mixer includes a diode ring (D1, D2, D3, D4) with respective balancing circuit portions for a local oscillator signal (LO) and a high frequency signal (RF) and a capacitively-loaded conductor branch (L3,L4) for an intermediate frequency signal (IF). In order to minimize conversion losses and obtain a high isolation between the local oscillator signal (LO) and the high frequency signal (RF), each balancing circuit portion comprises a first coupler including two strip lines (L11, L12; L31, L32) and a second coupler constructed as an interdigital coupler (L21, L22, L23, L24; L41, L42, L43, L44). The first coupler (L11, L12; L31, L32) of each balancing circuit portion is connected to a respective first symmetric input (1,3) of the diode ring and the second coupler is connected with a respective second symmetric input of the diode ring. Both couplers are connected with each other via one of their gates (14,24; 34,44). Two other gates (12,13; 32,33) of each first coupler (L11, L12; L31, L32) form asymmetric inputs for either the local oscillator signal (LO) or the high frequency signal (RF).