In the last few decades, the use of high-density polyethylene (HDPE) is continuously increasing such as HDPE pipes. These pipes are frequently used in the construction of long-buried infrastructures including water mains, sewers, and gas pipelines. These pipes are available in standards lengths and can be customized as per desired lengths using the fusion welding technique. In this article, the effect of changing the welding parameters such as temperature, heat, and soaking time on the performance of the fusion welding joint in HDPE is presented. The structural performance is measured by comparing the tensile strength of the unwelded and welded structure. Furthermore, the structural performance of extruded HDPE pipes and injection-molded HDPE fittings, such as elbows, tee-joints, and close end cap connections, are also discussed. The findings of this research are very useful in understanding and improving the structural performance of HDPE fusion welds with the help of comparative studies based on tensile strength on the welded joint in HDPE.