A remote control system comprising: a controlled device that is remotely controlled; and a mobile communication terminal that is configured to perform wireless communication with the controlled device, wherein the controlled device is configured to transmit, when accepting remote control, first data to the communication terminal, the mobile communication terminal is configured to transmit second data including a detail of remote control to the controlled device in response to the first data, and the controlled device is configured to perform a process determined by the detail of remote control included in the second data when a time elapsed since the first data is transmitted until the second data is received is less than a threshold value, further comprising: a server connected to the communication terminal via a network, wherein the mobile communication terminal is configured to transfer the first data received to the server, is configured to transmit the server the second data to the mobile communication terminal in response to the first data, and the mobile communication terminal is configured to transfer the second data received to the controlled device, wherein the mobile communication terminal is configured to display that communication is proceeding during communication with the server or during communication with the server and the controlled device. a controlled device that is remotely controlled; and a mobile communication terminal that is configured to perform wireless communication with the controlled device, wherein the controlled device is configured to transmit, when accepting remote control, first data to the communication terminal, the mobile communication terminal is configured to transmit second data including a detail of remote control to the controlled device in response to the first data, and the controlled device is configured to perform a process determined by the detail of remote control included in the second data when a time elapsed since the first data is transmitted until the second data is received is less than a threshold value, further comprising: a server connected to the communication terminal via a network, wherein the mobile communication terminal is configured to transfer the first data received to the server, is configured to transmit the server the second data to the mobile communication terminal in response to the first data, and the mobile communication terminal is configured to transfer the second data received to the controlled device, wherein the mobile communication terminal is configured to display that communication is proceeding during communication with the server or during communication with the server and the controlled device. a server connected to the communication terminal via a network, wherein the mobile communication terminal is configured to transfer the first data received to the server, is configured to transmit the server the second data to the mobile communication terminal in response to the first data, and the mobile communication terminal is configured to transfer the second data received to the controlled device, wherein the mobile communication terminal is configured to display that communication is proceeding during communication with the server or during communication with the server and the controlled device.