The increasing adoption of electric vehicles (EVs) in Indonesia, driven by fiscal incentives and infrastructure expansion, has introduced significant cybersecurity challenges, particularly integrating Internet of Things (IoT) technologies in EVs and charging systems. This study conducts a Systematic Literature Review (SLR) of 15 peer-reviewed publications from 2020 to 2025 to identify the most critical cybersecurity threats and evaluate mitigation strategies in IoT-based EV environments. This research identifies six recurring threat categories: false data injection (FDI), denial-of-service (DoS) attacks, remote hijacking, man-in-the-middle (MITM) attacks, firmware manipulation, and data breaches. Common mitigation strategies include machine learning-based intrusion detection systems, deep reinforcement learning (DRL), hybrid detection models, secure OTA firmware updates, and encrypted communication protocols. The research highlights the importance of scalable, low-cost solutions such as MIADRC and lightweight IDS for local deployment. It also emphasizes the need for national policy support and stakeholder coordination to ensure a secure and resilient EV ecosystem in Indonesia. These findings provide a foundation for future research and practical recommendations tailored to emerging EV markets.