近年來天然災害發生次數，不論颱風或是水災災害均有愈來愈頻繁的趨勢，未來颱風及洪水險保單勢必受到重視而作為分散危險的工具，因此若不對此保單承保範圍之「主力近因」予以釐清，則發生在民國90年7月30日桃芝颱風重創米堤飯店的保險理賠糾紛將會不斷重演。本研究將國內及國外一些主力近因原則之定義加以整理，釐清主力近因原則之觀念，並對主力近因原則的運用及危險事故與損害間的相互因果關係加以探討，透過個案研究，分析爭議之所在，明確了解保險事故、除外事故及未保事故之理賠時主力近因的判斷原則。藉由本研究，使得錯綜複雜的因果關係能夠獲得釐清，以利於產險理賠實務之運作，並減少產險之理賠糾紛。 Natural disasters take place more frequently in recent years. So the Typhoon and Flood endorsement will be regarded as an effective tool by the insured to disperse typhoon and flood risk in the future. Therefore, if the concept of proximate cause is not clearly, the claim dispute of loss to the Le Midi Hotel by typhoon Toraji on July 30, 2001 will recur constantly. We analyze the definitions of the“proximate cause” from domestic and foreign literatures to define the concept and doctrine of “proximate cause” clearly. The application of the proximate cause doctrine was discussed and made a study of causality between peril and loss. Through the cases study, we can analyze the claim disputes and clearly find out the judgments of proximate cause about the insured, excepted or uninsured perils. We also hope that the finding of this research can distinguish the intricate causality issue, benefit the claim process of non-life insurance industry, and reduce claim disputes between the insurers and the insureds.