戊酸是化学式为C₅H₁₀O₂的短链饱和脂肪酸。其它常用中文名称还有正戊酸、缬草酸等。 与其他低相对分子质量的羧酸类似，戊酸带有难闻的气味，类似于臭袜子的气味。它存在于多年生的开花植物valerian（，Valeriana officinalis）中，其英文名Valeric acid也因此得来。

戊酸主要用于合成戊酸酯。挥发性的戊酸酯带有宜人的气味，可用于香水和化妆品中。戊酸乙酯和戊酸戊酯有水果香味，用作食品添加剂。

戊酸与GHB和神经传递素GABA结构类似，与丙戊酸的差异仅在于3号碳上的侧链。

Valeric acid, or pentanoic acid, is a straight-chain alkyl carboxylic acid with the chemical formula C₅H₁₀O₂. Like other low-molecular-weight carboxylic acids, it has a very unpleasant odor. It is found naturally in the perennial flowering plant valerian (Valeriana officinalis), from which it gets its name. Its primary use is in the synthesis of its esters. Volatile esters of valeric acid tend to have pleasant odors and are used in perfumes and cosmetics. Ethyl valerate and pentyl valerate are used as food additives because of their fruity flavors.