A communication apparatus includes a communication unit, a first determination unit, a second determination unit, and a control unit. The communication unit communicates with an external apparatus via communication lines that conform to HDMI standard. The first determination unit determines whether the first data indicating that the external apparatus displays video data transmitted from the communication unit to the external apparatus is detected by the communication unit has received via a CEC line. The second determination unit determines whether a second data indicating that the external apparatus displays video data transmitted from the communication unit to the external apparatus is detected by the communication via a TMDS line. The control unit determines whether to transmit video data to the external apparatus based on at least one of a determination result obtained by the first determination unit and a determination result obtained by the second determination unit.