A hydrogen bond donor is the group that provides the polarised hydrogen atom (X–H) in a hydrogen bond, where X is a highly electronegative atom such as fluorine, oxygen, or nitrogen. The strong polarisation leaves the hydrogen with a substantial partial positive charge. The donor pairs with a hydrogen bond acceptor, which supplies the lone pair the hydrogen is attracted to.

氢键给体是在氢键中提供极化氢原子(X–H)的基团,其中 X 为氟、氧、氮等高电负性原子。强烈的极化使该氢原子带有相当大的部分正电荷。给体与氢键受体配对,后者提供氢原子所吸引的孤对电子。