有鑑於肥胖人口激增，減重需求大增，瘦身減肥一直是女性所關注的議題之一。然而，瘦身減肥意味著某些潛在的衝突，例如：少吃多動、美麗自信與損害健康等矛盾情結，這種矛盾情結正是雙岐態度的特徵。態度包含了情感、認知、行為意圖三種層面，在預測閱聽人的行為意圖時，態度往往是最佳指標。過去的研究發現雙岐態度的高低會影響閱聽人的訊息處理途徑，因此本研究企圖以雙岐態度理論與推敲可能性模式（elaboration-likelihood model，簡稱ELM）來解釋廣告訊息的強弱如何透過雙歧態度而影響廣告效果。 研究結果主要發現，廣告訊息的強弱論點有穩定且一致的主要效果，表示強論點的廣告訊息在廣告、瘦身與產品態度三方面都會產生較正向的評價。雙歧態度高低則無顯著差異，而在部分條件下，強弱論點與雙歧雙歧的交互作用達顯著差異，也就是說低雙歧的人對於強論點的廣告訊息有較正向的廣告效果反應，顯示出雙歧態度對廣告訊息的調節作用。此外，瘦身產品的物理或化學性質對瘦身廣告與瘦身產品的態度都顯著性的影響，女性對於化學性質的瘦身產品有較佳的廣告態度與產品態度。本研究結果隱含著雙歧態度未來研究發展之建議與廣告行銷上的實務策略，雙歧理論仍有待後續研究考證；而行銷業者則必須注意廣告訊息的編碼是否有效，另外，消費者與閱聽人的態度不僅是行為的最佳指標，也是調節廣告效果的要重因素。最後提出研究限制與後續研究發展。 / According to the increase of fatness population and the need of weight-loss, women always pay close attention to reduce weight. However, to lose weight means some potential conflicts, such as less assimilate and more exercise；beauty, confidence and the risk of ruin health. This kind of contradictory complexes are the typical characteristic of ambivalence attitude. On predicting the behavior attention of the audience , the best index is attitude which is composed of affection, cognition, and behavior. Past research has found the level of ambivalence influence the information process of the audience, for this reason, the present research designs to integrate ambivalence attitude and ELM to explain how the argument of AD influence the effects of AD by ambivalence. The main results of the study show the strong arguments of AD are stable and consistency and the ambivalence attitude have no impacts on the effect of AD. In particular situation, the ambivalence attitude has moderation on AD effects. Moreover, the attribution of weight-loss products made some differences evaluation on AD attitudes and product attitudes. The datum reveal women preference chemical weight-loss products, favor chemical weight-loss AD. The results imply that the improvement of ambivalence theory and the suggestions on practical marketing. Further, the attitude of the audience is not only the best index of behavior, but also the significant factor on moderating the AD effects. In conclusion, address the restriction of the present study and the direction of follow-up research.