<p>Provided are an application upgrade method and device, which are applied in the field of cloud computing and can guarantee normal operating of an application after upgrade. The application upgrade method is used for an application deployment server and comprises: receiving an application deployment request; determining an application deployment packet and an upgrade packet to be deployed; determining that the version of a first platform node is lower than the version requirement of an application node template to be deployed on a first platform node template; acquiring a first platform node upgrade packet satisfying the version requirement of the application node template to be deployed on the first platform node template; using the first platform node upgrade packet to upgrade the first platform node indicated by the identification of the first platform node; determining the identification of the application node to be upgraded; and using the application deployment packet to be deployed to upgrade the application node indicated by the identification of the application node to be upgraded. An application upgrade method and device are provided to be applied to the application upgrade of the field of cloud computing.</p>
