PPPoE（英语：Point-to-Point Protocol Over Ethernet），以太网上的点对点协议，是将点对点协议（PPP）封装在以太网（Ethernet）框架中的一种网络隧道协议。由于协议中集成PPP协议，所以实现出传统以太网不能提供的身份验证、加密以及压缩等功能，也可用于缆线调制解调器（cable modem）和数字用户线路（DSL）等以以太网协议向用户提供接入服务的协议体系。

本质上，它是一个允许在以太广播域中的两个以太网接口间创建点对点隧道的协议。

以Linux系统常用的pppd为例，支持PPP接口上面的IP、IPv6和IPX网络层协议。

The Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol for encapsulating PPP frames inside Ethernet frames. It appeared shortly after the year 2000, in the context of the boom of DSL as the solution for tunneling packets over the DSL connection to the ISP's IP network, and from there to the rest of the Internet. A 2005 networking book noted that "Most DSL providers use PPPoE, which provides authentication, encryption, and compression." Typical use of PPPoE involves leveraging the PPP facilities for authenticating the user with a username and password, predominately via the PAP protocol and less often via CHAP.