The present disclosure provides a system, a method, and a device for displaying a content item. The system includes: a video playing terminal, configured to obtain a video and play the video; a content item displaying client, configured to send a content item obtaining request for requesting to obtain a content item related to the video being played by the video playing terminal; and a content item preparation platform, configured to determine a current playing moment of the video played by the video playing terminal, select, from one or more content items corresponding to the video, a content item with a marking moment nearest to the current playing moment, and push the selected content item to the content item displaying client, where the content item displaying client is further configured to display the received content item.