Disclosed is a chip-to-chip interface using a microstrip circuit and a dielectric waveguide. A board-to-board interconnection device, according to one embodiment of the present invention, comprises: a waveguide which has a metal cladding and transmits a signal from a transmitter-side board to a receiver-side board; and a microstrip circuit which is connected to the waveguide and has a microstrip-to-waveguide transition (MWT), wherein the microstrip circuit matches a microstrip line and the waveguide, adjusts the bandwidth of a predetermined first frequency band among the frequency bands of the signal, and provides same to the receiver.