2-巯基乙醇（又称为β-巯基乙醇，1-硫代乙二醇;2-羟基乙硫醇;β-硫醇代乙醇）是一种有机化合物，其化学式为HOCH₂CH₂SH，英文通用缩写为ME或βME。它兼具乙二醇（HOCH₂CH₂OH）和乙二硫醇（HSCH₂CH₂SH）的官能团，为挥发性液体，具有较强烈的刺激性气味。βME通常用于二硫键的还原，可以作为生物学实验中的抗氧化剂。它被广泛使用的原因是它的羟基使它能够溶解于水中，并且降低它的挥发性。由于具有较低的蒸汽压，它的难闻的情况比起恶臭的硫醇要好得多。

2-Mercaptoethanol (also β-mercaptoethanol, BME, 2BME, 2-ME or β-met) is the chemical compound with the formula HOCH₂CH₂SH. ME or βME, as it is commonly abbreviated, is used to reduce disulfide bonds and can act as a biological antioxidant by scavenging hydroxyl radicals (amongst others). It is widely used because the hydroxyl group confers solubility in water and lowers the volatility. Due to its diminished vapor pressure, its odor, while unpleasant, is less objectionable than related thiols.