亚马逊弹性云端运算（英语：Amazon Elastic Compute Cloud，简称Amazon EC2） ，是由亚马逊公司提供的Web服务，是一个让用户可以租用云端电脑运行所需应用的系统。EC2借由提供Web服务的方式让用户可以弹性地运行自己的Amazon机器映像档，用户将可以在这个虚拟机上运行任何自己想要的软件或应用程序。

用户可以随时创建、运行、终止自己的虚拟服务器，使用多少时间算多少钱，也因此这个系统是“弹性”使用的。EC2让用户可以控制运行虚拟服务器的主机地理位置，这可以改善让延迟还有备援性例如，为了让系统维护时间最短，用户可以在每个时区都运行自己的虚拟服务器。Amazon.com以Amazon Web Services (AWS)的品牌提供EC2的服务。

Amazon Elastic Compute Cloud (EC2) forms a central part of Amazon.com's cloud-computing platform, Amazon Web Services (AWS), by allowing users to rent virtual computers on which to run their own computer applications. EC2 encourages scalable deployment of applications by providing a web service through which a user can boot an Amazon Machine Image to configure a virtual machine, which Amazon calls an "instance", containing any software desired. A user can create, launch, and terminate server-instances as needed, paying by the hour for active servers - hence the term "elastic". EC2 provides users with control over the geographical location of instances that allows for latency optimization and high levels of redundancy.