A smart key storage case for storing, in a cabin of a vehicle, a smart key that is a portable device of a keyless entry system of the vehicle, the smart key storage case comprising: a storage case main body configured to store the smart key and to shield a signal transmitted and received between an in-vehicle device and the smart key of the keyless entry system; a reception antenna disposed outside the storage case main body and configured to receive a call signal periodically transmitted from the in-vehicle device to an outside of the vehicle and an inside of the cabin at different timing; a transmission antenna disposed inside the storage case main body and configured to radiate the call signal received by the reception antenna to an inside of the storage case main body; a transmission path through which the call signal received by the reception antenna is transmitted to the transmission antenna; a switch (48, 50) provided in the transmission path and configured to switch a conduction/cutoff state of the transmission path; a radio communication unit configured to enable data communication with a portable radio communication terminal registered in advance outside the storage case main body; a controller configured to, when the radio communication unit receives predetermined data transmitted from the radio communication terminal, turn on the switch according to a reception situation of the predetermined data to switch the transmission path from a cutoff state to a conduction state; and a response signal relay section configured to radiate a response signal transmitted from the smart key in response to the call signal radiated from the transmission antenna inside the storage case main body to an outside of the storage case main body, wherein when the predetermined data is received by the radio communication unit, the controller identifies, based on a signal strength at a time of receiving the predetermined data, whether the radio communication terminal is present outside the vehicle or inside the cabin, and controls an on/off state of the switch so that when the radio communication terminal is present inside the cabin, the switch is turned on to switch the transmission path from a cutoff state to a conduction state, and when the radio communication terminal is present outside the vehicle, of a plurality of the call signals received by the reception antenna, the first call signal transmitted from the in-vehicle device to an inside of the cabin is cut off, and the second call signal transmitted from the in-vehicle device to an outside of the vehicle is selectively transmitted. a storage case main body configured to store the smart key and to shield a signal transmitted and received between an in-vehicle device and the smart key of the keyless entry system; a reception antenna disposed outside the storage case main body and configured to receive a call signal periodically transmitted from the in-vehicle device to an outside of the vehicle and an inside of the cabin at different timing; a transmission antenna disposed inside the storage case main body and configured to radiate the call signal received by the reception antenna to an inside of the storage case main body; a transmission path through which the call signal received by the reception antenna is transmitted to the transmission antenna; a switch (48, 50) provided in the transmission path and configured to switch a conduction/cutoff state of the transmission path; a radio communication unit configured to enable data communication with a portable radio communication terminal registered in advance outside the storage case main body; a controller configured to, when the radio communication unit receives predetermined data transmitted from the radio communication terminal, turn on the switch according to a reception situation of the predetermined data to switch the transmission path from a cutoff state to a conduction state; and a response signal relay section configured to radiate a response signal transmitted from the smart key in response to the call signal radiated from the transmission antenna inside the storage case main body to an outside of the storage case main body, wherein when the predetermined data is received by the radio communication unit, the controller identifies, based on a signal strength at a time of receiving the predetermined data, whether the radio communication terminal is present outside the vehicle or inside the cabin, and controls an on/off state of the switch so that when the radio communication terminal is present inside the cabin, the switch is turned on to switch the transmission path from a cutoff state to a conduction state, and when the radio communication terminal is present outside the vehicle, of a plurality of the call signals received by the reception antenna, the first call signal transmitted from the in-vehicle device to an inside of the cabin is cut off, and the second call signal transmitted from the in-vehicle device to an outside of the vehicle is selectively transmitted.