IBM系统网络架构（英语：Systems Network Architecture，缩写为SNA）由IBM公司在1974年该公司大型主机网络架构所订定的网络结构标准和通信协定。后来ISO（国际标准组织）使用IBM的SNA架构作为它的OSI模型（开放式系统架构）的原始模型架构，OSI 所包含七层架构为：

Systems Network Architecture (SNA) is IBM's proprietary networking architecture, created in 1974. It is a complete protocol stack for interconnecting computers and their resources. SNA describes formats and protocols and is, in itself, not a piece of software. The implementation of SNA takes the form of various communications packages, most notably Virtual Telecommunications Access Method (VTAM), the mainframe software package for SNA communications.