Light-up small molecule fluorescent dyes play an important role in modern analytical techniques, and they can be widely applied in biochemistry and biomedicine. Aptamers, including single-stranded ribonucleic acids and deoxyribonucleic acids, are molecules that have high affinity for, and can selectively bind to, a specific target, including ions, small molecules, cells, etc. Aptamers are selected in vitro using a process termed SELEX. Light-up dyes have excellent fluorogenic behavior because, although their baseline fluorescence is very low, their fluorescence quantum yield dramatically increases when they bind with a specific aptamer. Aptamer-dye pairs are used in biological imaging and chemical analysis because of their numerous advantages, including their low cost, small size, ease of modification, stability, and low immunogenicity. This paper reviews the progress that has been made in the selection of aptamers for use with light-up dyes and the applications of aptamer-based light-up dyes.