标准氢电极（英文：Standard Hydrogen Electrode，旧时用Normal Hydrogen Electrode，简称NHE，现已停用），简称SHE，是构成标准电极电势（）基准的工作电极。在25℃时，它的绝对电位大约为4.44±0.02V，但为了给所有电极反应的电动势设立一个基准值，在任意温度下氢电极的标准电极电势都定义为零。其他电极的电势都是相对于标准氢电极而确定的。

氢电极的氧化还原半反应式如下：

这个半反应是在镀有铂黑的处于标准状态（气体压强为1大气压、离子或分子的活度为1mol/L的溶液）的铂电极上发生的，相应的能斯特方程为：

The Standard hydrogen brady theory electrode (abbreviated SHE), is a redox electrode which forms the basis of the thermodynamic scale of oxidation-reduction potentials. Its absolute electrode potential is estimated to be 4.44 ± 0.02 V at 25 °C, but to form a basis for comparison with all other electrode reactions, hydrogen's standard electrode potential (E) is declared to be zero volts at all temperatures. Potentials of any other electrodes are compared with that of the standard hydrogen electrode at the same temperature.