PT DENSO INDONESIA is a manufactured industry of vehicles spare parts. One of the products
is spark plugs that contain insulator, housing, talk ring, ring form, gasket ring, nut lathe
terminal, washer, and cup cutting. The questions formulated are how the company controlled
the spark plugs productions, how the company arranged the economic order quantity / EOQ,
safety stock, re-order point, maximum inventory, and total inventory cost, and how effective
EOQ in controlling the company’s stock. The analysis method used in this study is EOQ. Based
on the result, the EOQ set by the company was 12.560 units, the safety stock was 34.927 units,
the spark plugs ordered 170 times in a year with 46.615 units of the stock, and maximum
inventory was 47.487 units.