P T. Fajarindo Faliman Zipper is a manufacturing company engaged in the production of zippers. The product under study is a long chain product. The problem being faced by the company is that the long chain production has not reached the production target. The purpose of this study was to evaluate the results of production output in the Long Chain Division at PT. Fajarindo Faliman Zipper at this time and gave a proposal to improve the output of production results in the Long Chain Division to achieve production targets through resource allocation at PT. Fajarindo Faliman Zipper. Long chain production results in the current real system, have an average of 798 units per week, while the long chain production target is 884 units per week. In identifying bottleneck problems that occur on the production floor, the Theory Of Constraint and Simulation Approach are used to allocate resources on the production floor. The data used in this study came from direct observations and interviews with the company. The data from these observations were then tested for uniformity and adequacy to produce 25 observation times for the production process and transportation time. In analyzing the location of the bottleneck, it is necessary to data production process time using Theory Of Constraint analysis. From the results of the Theory Of Constraint calculation, it is known that bottlenecks occur in yarn knitting machines, ribbon knitting machines, sewing machines, dyeing areas and rubbing machines, so additional additions are needed. 1 machine, the ribbon knitting machine required the addition of 2 machines, the sewing machine required an additional 6 machines, the dyeing area required an additional 4 machines and the scouring machine required the addition of 4 machines. The results of the Theory Of Constraint calculations are used as the basis for making a proposed model through a Simulation Approach. In making a simulation, the first step is to build a model that describes the initial conditions of the production floor. After running the simulation, it is known that the simulation output obtained from the general report is 747 long chain units. After getting the results from this initial model, the next step is to develop the model by making a proposed scenario. There are 10 proposed scenarios and only 4 scenarios that meet the production target_ These four scenarios are used as a proposed model and a bonferroni test and additional profit analysis are carried out. Based on the results of the comparison between the initial model and the four models proposed both from the production output, the percentage of resource utility, the Bonferroni test, and the amount of additional profit, the best proposed model is the third proposed model with the proposed addition of 2 work shifts, the addition of 6 sewing machines. machine units, and the addition of 1 machine unit of yarn knitting machine. The third proposed model produces a production output of 885 units with an additional profit of IDR 2,219,856.00, and has an average resource utility of 95.05% which increases by 0.28% from the average utility of the initial model. Keywords: Theory Of Constraint, Bottleneck, Simulation.