Fiber-wound composite cylinder is widely used in many fields because of its light weight. However, at present, there is still a lack of research on the impact damage of the winding layer of winding gas cylinder. In this paper, we investigate the impact damage mechanisms in Type IV fiber-wound composite gas cylinders using acoustic emission (AE) technology. Specimens were subjected to controlled impacts from various heights to introduce pre-damage, followed by stepwise pressurization until bursting. AE sensors were deployed to monitor real-time signals during the pressurization process, capturing amplitude, energy, and cumulative signal characteristics. Results reveal that cylinders impacted from greater heights exhibited more severe initial damage, as evidenced by earlier high-amplitude AE signals and higher energy peaks during pressurization. Specimens with higher impact energy also showed lower bursting pressures and catastrophic failure modes. The findings highlight the sensitivity of AE technology in detecting micro-defects and tracking damage evolution. This study provides a foundation for the evaluation of impact-induced damage in composite gas cylinders and informs the development of safer designs.