The construction sector ranks among the most energy-intensive industries globally, making it essential to comprehend its energy demands, particularly as urbanisation accelerates across China, accompanied by the rapid expansion of building development. In light of this, conserving energy at all stages of construction has become increasingly critical to curtail consumption and promote sustainability. The present study seeks to systematically examine and synthesise the key factors that affect energy conservation across the entire lifecycle of construction projects. It further evaluates international and regional trends, with particular focus on China, and investigates the role of energy-efficient technologies, policy frameworks, and awareness initiatives in supporting the adoption of energy-saving practices. To achieve these objectives, the study employed the PRISMA checklist to guide a systematic literature review. Following rigorous application of inclusion and exclusion criteria, twelve relevant studies were selected for analysis. The thematic analysis of these studies facilitated the identification of recurrent concepts. The findings reveal that the integration of energy-efficient technologies, such as Building Information Modelling (BIM), Life Cycle Assessment (LCA), and smart building systems, can significantly lower energy usage across various construction phases. The implementation of these technologies has been driven by financial incentives and regulatory measures, with such influences being particularly notable in China. The research highlights that energy-efficient technologies can be effectively applied during construction, post-construction, and operational phases when supported by robust government policies and enhanced stakeholder awareness.