电浆振荡（Plasma oscillation），又称作朗缪尔波（以欧文·朗缪尔命名），是在如电浆或金属导体中的电子密度的快速振荡。在自由电子气的介电函数中，这个震荡可以被形容为是一不稳定现象。频率只稍微和波长有关。这些震荡量子化后所产生的准粒子称为电浆子。

朗缪尔波是由美国物理学家欧文·朗缪尔和Lewi Tonks于1920年代发现。这和金斯不稳定性波的形式类似，金斯不稳定性波是由静态介质中的重力不稳定性所造成的。

Plasma oscillations, also known as "Langmuir waves" (after Irving Langmuir), are rapid oscillations of the electron density in conducting media such as plasmas or metals. The oscillations can be described as an instability in the dielectric function of a free electron gas. The frequency only depends weakly on the wavelength of the oscillation. The quasiparticle resulting from the quantization of these oscillations is the plasmon.