A marking assist device includes a memory, a storage that stores an image that records a competition in which a player performs a plurality of skills in a time sequence, and a processor coupled to the memory and configured to acquire a first marking result and a second marking result, the first marking result being marking of each of the plurality of skills based on sensor data on the performing player, the second marking result being inputted by a referee, display first discriminators of the skills included in the first marking result and second discriminators of the skills included in the second marking result while associating the first discriminator with the second discriminator, and when any discriminator is selected from the displayed discriminators, identify a video associated with selected discriminator from the images and displays the identified video.