Abstract: Using the amorphous solid dispersion (ASD) technology, poorly water-soluble drugs can be formulated into high-energy amorphous forms. After oral administration, a kinetic supersaturated solution is formed in the gastrointestinal tract, and oral bioavailability is thus effectively improved. As important components of ASDs, pharmaceutical excipients affect the supersaturation of ASDs. Therefore, it is significant to clarify the effects of various types of pharmaceutical excipients on the supersaturated solutions for the development of ASDs. This paper reviews the effects of polymers, small-molecule excipients, and porous materials on the supersaturated solutions formed after dissoptlution of ASD with an emphasis on the mechanisms of various types of pharmaceutical excipients on the supersaturated solutions, providing theoretical guidance for the rational selection of medicinal excipients in the development of ASDs.