This paper provides a comprehensive review of the security risks associated with 4G/5G networks in power systems, focusing on their architecture, service characteristics, and emerging challenges. The study highlights key vulnerabilities, including wireless access threats, core network API abuses, network slicing isolation failures, edge computing risks, and management-level issues such as cross-domain coordination and supply chain security. To mitigate these risks, the paper proposes technical countermeasures such as lightweight cryptographic algorithms, AI-driven intrusion detection, and SDN-based dynamic routing. It also discusses the application of advanced technologies like Quantum Key Distribution and digital twins for future-proof security frameworks. Additionally, the paper identifies gaps in standards and policies, advocating for interdisciplinary collaboration and unified industry regulations to enhance the resilience of power communication systems.