A medical image assistance system and a medical image assistance method are provided. During a medical process, an image capturing apparatus located at a local location captures a first image and transmits the first image to a control device located at the local location, and the control device transmits the first image captured by the image capturing apparatus to an electronic apparatus located at a remote location. The electronic apparatus performs a marking operation on the first image to generate a second image, and transmits the second image to the control device. The control device transmits the second image to a head-mounted display apparatus located at the local location so that the head-mounted display apparatus simultaneously displays the second image and a real-time local image. The first image and the second image are at least partially the same in content.