A content transmission device for transmitting a digital content to other device connected via a network, including a receiving unit that receives the digital content accompanied with a piece of copy control information indicating a condition of restricting the digital content from being copied, a communication processing unit that transmits and receives the digital content or control commands to and from the other device, a connection determining unit that determines whether the other device is present on an intra-residential network connected by the content transmission device, and a control unit that controls the receiving unit, the communication processing unit, and the connection determining unit, in which the control unit does not output the digital content received by the receiving unit from the communication processing unit to the other device in a case where the other device is determined not to be installed at an inside of a residence.