Linear low-density polyethylene (LLDPE) is widely used in many fields like packaging and film due to its chemical resistance and high tensile strength. This review mainly introduces the preparations and applications of LLDPEs produced by Ziegler-Natta catalyst, metallocene-based catalyst, and late transition metal catalyst, respectively. The improved mechanical and conductivity properties of LLDPE by Ziegler-Natta catalysts, higher activity of the metallocene-based catalysts and high performance of LLDPE directly produced by late transition metal were highlighted. The enhancement of the resistance, flexibility, transparency properties, and yield is achieved using those catalysts and mild conditions. This also leads to more applications in electrical, medical, and surgical areas and can reach an industrial scale.