域名系统安全扩展（英语：Domain Name System Security Extensions，缩写为DNSSEC）是Internet工程任务组 （IETF）的对确保由域名系统 （DNS）中提供的关于互联网协议 （IP）网络使用特定类型的信息规格套件。它是对DNS提供给DNS客户端（解析器）的DNS数据来源进行认证，并验证不存在性和校验数据完整性验证，但不提供或机密性和可用性。

The Domain Name System Security Extensions (DNSSEC) is a suite of Internet Engineering Task Force (IETF) specifications for securing certain kinds of information provided by the Domain Name System (DNS) as used on Internet Protocol (IP) networks. It is a set of extensions to DNS which provide to DNS clients (resolvers) origin authentication of DNS data, authenticated denial of existence, and data integrity, but not availability or confidentiality.