The present disclosure relates to a 5th generation (5G) or pre-5G communication system for supporting a higher data transmission rate than a 4th generation (4G) communication system such as Long-Term Evolution (LTE). The present disclosure provides a device for variable signal attenuation equipped in a stack-up structure inside an RFIC. The device for signal attenuation comprises: a first transmission line positioned on a first layer inside the RFIC; a second transmission line positioned on a second layer, which is adjacent to the first layer, and electromagnetically coupled to the first transmission line; and a control unit. The first transmission line comprises an impedance control unit on one side. The control unit can variably control the impedance control unit.