水杨醛，也称邻羟基苯甲醛、2-羟基苯甲醛，分子式为C₆H₄CHO-2-OH，室温下为无色油状液体。

水杨醛是制取多种螯合配体的原料，可由苯酚与氯仿在氢氧化钠溶液中加热发生瑞穆尔-悌曼反应制备：

水杨醛可发生多种反应：

制备：

由苯酚和氯仿在氢氧化钠溶液中反应得到。改进的制法是由邻甲苯酚与氧氯化磷或光气反应、再经水解制得。也可以由水杨酸电解还原或由水杨酰卤催化还原制得。

Salicylaldehyde (2-hydroxybenzaldehyde) is the organic compound with the formula C₆H₄CHO-2-OH. Along with 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, it is one of the three isomers of hydroxybenzaldehyde. This colorless oily liquid has a bitter almond odor at higher concentration. Salicylaldehyde is a key precursor to a variety chelating agents, some of which are commercially important.