A device, method, and medium for expressing content dynamically are provided. The device for expressing content dynamically includes: a background-music-analyzing module for analyzing background music; an image-unit-group-adjusting module for adjusting attributes of a plurality of image unit groups including at least one content element and image effect element included in each image unit group according to the analyzed background music; a time-adjusting module for adjusting a length of time taken to express the attribute-adjusted image unit groups and the at least one content element included in each image unit group according to the analyzed background music; and a control module for displaying the time-adjusted image unit groups and the at least one content element included in each image unit group.