存貨通常是預期可以在一段營業期間內被出售，因此在企業的資產負債表中被列為流動資產，但過多的存貨將產生資金積壓、增加儲存空間、跌價與過期呆帳損失等風險。反之若存貨過少，需以較高成本緊急排單生產來滿足客戶的需求，甚至可能因違約而影響企業的商譽。然而合理的存貨依產業別與利潤率而異，利潤率越高的產品，相對可接受較高的存貨與存貨週轉天數，產品少量多樣、需求不確定性高、生產週期長且原物料供應鏈變異大之高階醫療器材即屬之，這種高度需求和供給的不確定性對於生產和存貨管理帶來了挑戰，建立安全庫存以確保供貨是企業常採用方法。然而實際執行效果可能受到外部環境變化、市場競爭策略、財務衡量、經營結構調整、生產與存貨管理人員是否及時有效因應等因素的影響。本研究將以國內最具代表性之醫療器材公司進行個案研究，個案公司在2017年因公司營運結構改變，加上外在環境變化衝擊，更凸顯出供需不確定性對存貨的影響，平均存貨成本高達每月營收的3倍以上，存貨週轉天數更超過300天，持續的淨現金流出造成財務壓力。研究將由實務角度探討該公司從2019年到2022年採取之各項生產與存貨管理管理措施及其改善效果，可提供面對類似問題企業的參考。研究過程透過收集研究期間之銷售預估、實際銷售、生產入庫與各種存貨資料，作為比較分析的基礎，最後歸納出在供需不確定下要維持短交期、不缺貨的銷售競爭策略，有效的存貨管理改善措施包括:依生產週期與生產型態定義安全庫存量、市場需求滾動式預測應用、更即時產出與在製工時資訊提供以提高生產彈性與效率、以未來存貨週轉概念作為存貨指標及原物料採購依據。執行結果使得存貨成本在2019年達到高點後逐步下降，到2022年累計降低了約15%，期間平均銷售累計成長了約42%，平均總存貨週轉天數由396天降低到237天。

High-end medical device are characterized by small quantities and diverse types, high demand uncertainty, long production cycles, and significant variability in the supply chain of raw materials. This high level of demand and supply uncertainty presents challenges for production and inventory management. Establishing safety stock to ensure supply is a commonly adopted strategy by companies. This study will conduct a case study on the most representative medical device company in the domestic market which encountered an issue of excessive inventory. The research will explore the various production and inventory management measures adopted by the company from 2019 to 2022 and their improvement effects from a practical perspective. It aims to provide a reference for companies facing similar issues.
The research process involves collecting sales forecasts, actual sales, inbound quantities, and various inventory data during the study period as the basis for comparative analysis. Ultimately, the study will summarize effective inventory management improvement measures under the sales competition strategy of maintaining short lead times. These measures include redefining safety stock levels based on production cycles and production types, applying rolling forecasts of market demand, providing more timely production output and work-in-process information to enhance production flexibility and efficiency, introducing the concept of future inventory turnover as an inventory indicator and a basis for raw material procurement. The implementation results show that inventory costs cumulatively reducing by approximately 15% and the average total inventory turnover days dropping from 396 days to 237 days.

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