以太网供电（Power over Ethernet，简称PoE）也称PoE供电，是一种可以在以太网路中透过双绞线来传输电力与数据到设备上的技术。

透过这项技术可使包括网络电话、无线基地台、网络摄影机、集线器、电脑等设备都能采用PoE技术供电，由于能借由以太网路获得供电的电子设备无需额外的电源插座就可使用，所以同时能省去配置电源线的时间与金钱，使整个设备系统的成本相对降低。而目前全球均普遍采用RJ-45网络插座，因此各种PoE设备都具备兼容性。这项技术常常被跟同样也是在同一条电缆上接收电源与数据（虽然是模拟数据）的传统电话网络（POTS）来对照。PoE不需要更改以太网路的缆线架构即可运作，所以采用PoE系统不但节省成本易于布线安装还具备了远程通电、断电的能力。

Power over Ethernet or PoE describes any of several standardized or ad-hoc systems which pass electrical power along with data on Ethernet cabling. This allows a single cable to provide both data connection and electrical power to devices such as wireless access points or IP cameras. Unlike standards such as Universal Serial Bus which also power devices over the data cables, PoE allows long cable lengths. Power may be carried on the same conductors as the data, or it may be carried on dedicated conductors in the same cable.