A medical observation apparatus includes: an image sensor that outputs an image signal; a transmission signal processing unit configured to convert an electrical signal into serial electrical signals and change number and a destination thereof; an optical signal conversion unit configured to convert the serial electrical signals into optical signals; optical transmission paths configured to transmit the converted optical signals; an electrical signal conversion unit configured to convert the transmitted optical signals into serial electrical signals; a received-signal processing unit configured to performs a predetermined image processing on the received serial electrical signals to generate and output a display image signal to a display device, and detect transmission failure of the optical signals in the optical transmission paths; and a control unit configured to control changing of the number and the destination of the serial electrical signals in accordance with a result of detection of the transmission failure.