Abstract: This paper provides a systematic and comprehensive review of the research progress on gallium (Ga)-based liquid metals (LM). The study covers a wide range of topics, including the composition of Ga-based LM, their complex phase transition processes, diverse application fields, significant advantages, existing challenges, and effective modification strategies. Due to their unique physical and chemical properties, Ga-based LM have attracted significant attention across various industries. Their phase transition process is highly complex, involving a series of physicochemical changes and atomic rearrangements and interactions at the microscopic level. These materials exhibit remarkable advantages, such as high thermal conductivity and large phase change latent heat, enabling them to efficiently transfer and store heat in thermal management applications. They provide excellent solutions for heat dissipation in electronic devices. Additionally, Ga-based LM show great potential in energy storage, enhancing the efficiency of energy storage and conversion. However, their applications also face some challenges, such as corrosion of other materials, which may affect the lifespan of devices in contact with them, and the occurrence of undercooling, which limits their use in certain scenarios. To address these issues, researchers have explored alloying and composite modification strategies to improve their performance. Looking ahead, Ga-based LM is expected to make breakthrough progress in micro-mechanism exploration, further performance optimization and new application areas. This review aims to provide a comprehensive and valuable reference for research and applications in related fields.