This paper provides a comprehensive security analysis of the Electric Vehicle (EV) charging service in Smart Grid (SG) environment (i.e. the “smart” EV charging application). It first describes three EV charging scenarios, at home, at work and at public places. Based on these use-case scenarios, the paper presents a model for smart EV charging, consisted of application entities and interactions among them. It then illustrates potential message types communicated among these entities. Based on this model and the exchanged messages, the paper analyses security problems and potential security threats imposed on the entities, which leads to the specification of a set of security and privacy requirements. These requirements could be used to guide the future design of solutions for secure smart EV charging systems and/or a risk/impact assessment of such systems.