P PT. Quantumplast Industry is a manufacturing company engaged in the field of plastic packaging manufacturing such as plastic bottles, plastic cups and all parts that form a bottle such as bottle caps and inner plugs. The purpose of this final project research is to determine the optimum setting for the YIZUMI 160T injection machine to improve the production capability of bottle caps from PT. Quantumplast Industry by using one of the methods in experimental design, namely the 2k Factorial Method. The purpose of this research is to determine the optimum setting for the YIZUMI 160T Injection machine in order to increase the value of its production capability in producing 20 mm bottle caps. The initial step of this research is to first determine the variables that cause the bottle cap to be rejected. From the results of interviews and brainstorming with the head of the production department, it was determined that the response variables in the study were the diameter and thickness of the bottle cap. After these variables were determined, it was also determined what caused the variables not to be in accordance with the standards. Then, variable data was taken for calculations to determine the optimum setting for the machine. Then continued with the feasibility of the measuring instrument and it was found that the measuring instrument was feasible. Then continued with the normality test. After it was known that the data was normally distributed, the research was continued with the first order optimization experiment. And the calculation results obtained the optimum machine setting, namely 236.1 ° C for the temperature factor and 48.6 bar for the pressure factor.