A method and an apparatus for controlling video output, where the method includes detecting in real time, by a security controller, whether an output resolution configured in a video display controller and a high-bandwidth digital content protection (HDCP) encryption status configured in a high-definition multimedia interface (HDMI) satisfy an HDCP requirement of a video, and when the HDCP requirement of the video is not satisfied, sending, by the security controller, an instruction to the video display controller instructing the video display controller to stop outputting the video. Hence, when the HDCP requirement of the video is not satisfied the output video is insecure such that the security controller sends the instruction to the video display controller instructing the video display controller to stop outputting the video. Therefore, security of the video output is ensured.