The manufacturing process in its earliest form, consisted only of one skilled worker and his assistant but, after the industrial revolution, the manufacturing process became a large-scale industry. The factory system was first adopted in Britain at the beginning of the industrial revolution in the late 18th century. The concept for making composites is with open and closed mold. The purpose of the study is to study the methods by scientific researchers in the combination of polypropylene polymer with natural source material, Kenaf. It was found that almost all researchers use the same technique, namely the process of hot press and injection molding (after compounded). The hot press process is also known as compression molding or matched die technique. This process is similar to the sheet metal forming process. The method of blending using a compound machine combine two or more ingredients into one homogeneous mass in a continuous process. From the process, a pallet is produced, then from a pallet-shaped material, the injection molding method is used to produce a sample or dumbbell. Every study has proven the effectiveness of the mixture as well as its manufacturing techniques, but it ends in research arae. It is a benefit if every study can be continued by producing products that can be used in the industry. This usability will encourage researchers to explore simpler but less costly manufacturing methods or techniques.