In accordance with an embodiment, described herein is a system and method for supporting Enterprise Java Bean (EJB) and other application types in a multitenant application server environment. The system includes an application server domain with a plurality of partitions, an EJB application, and a plurality of partition-aware server components that interact with the EJB container. The EJB application includes partition-specific code deployed as a separate instance to each partition, and shareable resources across two or more partitions. The system can additionally delegate resource-heavy processing functions of each EJB application to one or more of the server components. At runtime, the system receives a request for an EJB application in a particular partition, and creates an object to hold information of the particular partition. The server components, when invoked by the EJB container, obtains the partition information and execute in a context of the particular partition.