Production problem is one of the most important issue for every company because that problem is directly related to company’s profit. On the other hand, continuity of production process is influenced by availability of raw materials which will be processed in production activities. However, many companies still cannot fix the quantity of raw materials they should have. If the raw materials provided are exceedingly, it will increasing storage costs, in te opposite if the raw materials are provided too little, the company will face the risk that they cannot fulfill in the high demand. In this case, the raw material inventory control needed to maintain the continuity of the production process. PT Starlight Garment Semarang in producing their garment product, needs kind of fabric as their main raw material such as: 100% cotton, 100% rayon, 100% polyester, 55% linen 45% rayon, 55% linen 45% cotton, etc that imported from other countries. Based on the data of 2015 , the most fabric used in PT. Starlight Garment Semarang is 100% cotton. PT. Starlight Garment Semarang do not meet the criteria of good inventory management, they only order raw material according to their estimated needs every time they get orders from buyers. This research will carry out data processing about Economic Order Quantity Method and Period Order Quantity Method to compare with inventory management that is used in PT. Starlight Garment Semarang. The collected data in this researched are raw material of fabric 100% cotton consumption period in 2015, raw materials ordering cost, raw materials storage cost and lead time for ordering raw materials. The result of this research is Economic Order Quantity produce the minimum total inventory cost in the amount of Rp.31.862.945 or 86,4% more efficient compare to inventory management that is used in PT. Starlight Garment Semarang.