FIELD: electrical engineering. SUBSTANCE: invention relates to the technique of ultrahigh frequencies, in particular to directional couplers. The compact directional coupler includes a dielectric substrate, one surface of which is metallized, and on the other, the first input of the first low-pass filter is connected to the first input of the device and the second input of the fourth low-pass filter, the second input of the first low-pass filter is connected to the second input of the device and the first input of the second low-pass filter, the second input of the second low-pass filter is connected with the third input of the device and the first input of the third low-pass filter, the second input of the third low-pass filter is connected to the fourth input of the device and the first input of the fourth low-pass filter. At the same time, cavities with a depth not exceeding the thickness of the substrate are made on the side of the metallized surface under the capacitive elements of the filters, while the walls of the cavities have a metallized layer. EFFECT: expansion of the arsenal of miniature diagram-forming circuits, as well as a reduction in the size of directional couplers and an expansion of the miniaturization capabilities of such devices without the use of multilayer printed circuit board technology. 1 cl, 5 dwg.