The inventory control of material at Perumda Tirta Kanjuruhan experienced overstock in the packaging of 600 ml bottles, as evidenced by the year-end stock in large quantities remaining unused from 2020 to 2022. This indicates the need for appropriate material inventory control for the 600 ml bottle packaging. The objective of this research is to forecast the demand for Bottled Drinking Water (AMDK) products and the lead time for material ordering for the next period, determine the optimum quantity for material orders, and assess the total inventory costs between the current condition and the proposed research. This study utilizes the Monte Carlo Simulation method and Probabilistic Economic Order Quantity (EOQ). Monte Carlo Simulation is employed to predict the demand for AMDK products and lead time for material ordering in the upcoming period. Meanwhile, Probabilistic EOQ is conducted to determine the optimal order quantity for each order. Primary data collection is carried out through observations and interviews in the AMDK and Finance units. Secondary data is obtained from company data and reports, literature reviews, as well as other reference sources. The required data for this research includes historical data on the demand for AMDK products and lead time for material ordering from January to December 2022, as well as data on material inventory costs. The research results indicate that the proposed method is more optimal than the current condition, as evidenced by the lower total inventory cost.