GaN with a wide band gap, high quantum efficiency, excellent thermal stability, and radiation resistance is important role in high frequency, high power electronics, and UV photoelectron devices. In this study, we present a novel approach by utilizing high-energy N plasma as the N source for synthesizing the GaN films with higher crystalline quality. This process occurs at a relatively low temperature of 850 °C, utilizing the economical and eco-friendly plasma-enhanced chemical vapor deposition (PECVD) method. Furthermore, the effects of N2 flux on the crystalline quality of the films, growth rate and optical characteristics are investigated. The results reveal that an increase in N2 flux enhances both the film growth rate and crystalline quality by boosting the kinetic energy of reacting atoms. Nevertheless, a further increase in N2 flux results in excessive nucleation rate, preventing atoms adsorbed on the substrate from migrating to appropriate positions. Consequently, the films grow in random directions, leading to a decline in crystalline quality. The GaN films prepared in this study achieve a carrier concentration of 2.19×1018 cm-3 and mobility of 5.17 cm2·V-1·s-1, demonstrating significant potential for optoelectronic device applications.