Inventory control is one of the important parts of any business organization. This article investigates the sensitivity analysis of an inventory model to increasing type demand for degrading items. In this inventory system, three parameters of the spoilage rate of the Weibull distribution are assumed and shortages are allowed with a partial delay rate. To get the optimal order quantity and optimal range of the average total cost function and this is important for proper coverage, consider numerical examples that confirm the actual use the results of this research work. Finally, the results show that the sensitivity analysis of the optimal solution for the system parameters is performed.