Abstract: Smart Card is a card with an embedded microprocessor inside the card. It can be programmed to create application, perform task and store information. Smart Card has a protocol called Application Protocol Data Unit (APDU), used to control data communication process. JavaCard is one of a technology in developing Smart Card. JavaCard is based on Java programming language to create JavaCard application. Since, the year 2006 University of Indonesia has been distributed smart cards to the new students, in order to provide a better and integrated services, using state of the art technology. The smart card is used for student’s identification with biometric information, library card, attendance card, e-parking, university bike utilization, bus way utilization and other facilities such as smart health application and e-wallet in the future. Until now the smart card has been distributed to more than 40000 students. In this research, a JavaCard application called Smart Health has been developed on the University of Indonesia`s Smart Card. This application has 2 functions. First, to read medical records from JavaCard and second, to write medical records into the JavaCard. Medical record which will be saved in the JavaCard was split into 6 categories. Smart Health application has 3 main parts, JavaCard applet, connector applet and terminal module. JavaCard applet is a program to control the reading and writing process on JavaCard. It also, controls JavaCard memory allocation. Connector applet is an interface program to connect the JavaCard applet with the terminal module. Terminal module is a Graphical User Interface (GUI) module. User interacts with the Smart Card application using this module. Performance analysis of this application focuses on the JavaCard memory allocation, APDU role on data traffic, data process, memory optimalization and application speed. In addition, we also analyze further development of this Smart Health application. The result of the analysis shows that JavaCard applet programming, APDU arrangement to process operation and memory allocation are the keys in building a JavaCard application.