In the modern world, climate change and global warming are serious problems. The thermal management of the human body under these conditions, especially during physical activity and work, is crucial. Hot weather conditions with intense metabolic activity lead to a critical health and safety situation. Reducing heat stress in workers who work outdoors or in hot environments has always been a challenge for occupational health and safety experts. The pivotal solution is to use personal cooling garments (PCGs) to build confidence in the safety and health of workers. This review study summarizes the mechanisms of 12 types of PCGs and discusses PCM garments as the most widely used PCGs. The importance of enhancing the effectiveness of PCMs with nanoparticles and biomass-derived porous carbon materials has been noticed. Furthermore, performance indicators and equations, the methods of evaluating the performance of cooling garments and the advantages or disadvantages of using these methods, factors affecting the cooling efficiency of PCM garments, and the application of PCM in textiles have been discussed. Afterward, the challenges and future trends in the design of PCM garments are introduced. The result of this review research can be helpful in the thermal management of the human body, especially for workers, by designing cooling garments with better efficiency and ultimately reducing energy consumption to cool the entire work environment.