有线等效加密（英文：Wired Equivalent Privacy，缩写：WEP），又称无线加密协议（英文：Wireless Encryption Protocol，缩写：WEP），是个保护无线网络信息安全的体制。因为无线网络是用无线电把消息传播出去，它特别容易被窃听。WEP的设计是要提供和传统有线的局域网路相当的机密性，而依此命名的。不过密码分析学家已经找出有线等效加密几个弱点，因此在2003年被实现大部分IEEE 802.11i标准的Wi-Fi Protected Access淘汰，又在2004年由实现完整IEEE 802.11i标准的WPA2所取代。有线等效加密虽然有些弱点，亦足以吓阻非专业人士的窥探。

Wired Equivalent Privacy (WEP) is a security algorithm for IEEE 802.11 wireless networks. Introduced as part of the original 802.11 standard ratified in 1997, its intention was to provide data confidentiality comparable to that of a traditional wired network. WEP, recognizable by the key of 10 or 26 hexadecimal digits, was at one time widely in use and was often the first security choice presented to users by router configuration tools.