丙三醇又称甘油，结构简式为HOCH₂CHOHCH₂OH或C₃H₅(OH)₃，分子式为C₃H₈O₃。

丙三醇是无色无臭有甜味的黏性液体，沸点为290℃，吸水性很强。

Glycerol /ˈɡlɪsərɒl/ (also called glycerine or glycerin; see spelling differences) is a simple polyol (sugar alcohol) compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. It is widely used in the food industry as a sweetener and humectant and in pharmaceutical formulations. Glycerol has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature. The glycerol backbone is central to all lipids known as triglycerides.