近年來，日本銳意推動地方分權改革，希冀挽救日益衰退的政治經濟赤字以及人民對政府的信任赤字。除了提昇行政效率之外，其更重要的目的便是深化民主政治。然而面對地方分權後的地方自治團體的規模可能無力承擔自治的問題，所以日本政府進行大規模的「市町村合併」。同時，為了促進政治過程中的民眾的政治參與，在合併的過程中增加住民投票制度的選項。在東亞國家當中，如何深化民主一直是不容易的事情，而日本這種嘗試值得觀察，此為本研究的問題意識。 本研究以日本地方自治體合併中的住民投票制度的運用為中心，枕日本「市村町合併」之沿革與目的、其現行之手續與住民投票在其中所扮演之角色與意義、以及「市町村合併」中的住民投票的制度與效果進行探討。 日本地方分權改革係希冀將由中央政府主導的由上而下轉型為由下而上的國家政治體制。然而這並不容易。即使在號稱地方自主的「市町村合併」的過程裡，也可以觀察到中央強勢主導的影子。同樣地，住民投票也並未在「市町村合併」中產生重大的決策影響。雖說如此，其宣示的意義大於實質的效果，日本柱深化民主所邁進的艱難的一步，其精神與經驗卻值得面對全球在地化風潮的台灣學習。

In recent years, Japanese government promotes decentralization reform to restore their democratic deficit. The purpose of this policy is not only to enhance the administration efficiency, but also to consolidate the democracy. To prepare the local self-governing body for the true local autonomy, Japanese government promotes the municipal amalgamation at the same time. Meanwhile, for the more political participation, Municipal Referendum is decided to set into the process of municipal amalgamation by government. It is not easy to consolidate democracy in the East Asia countries, so it is worthy to observe this case of Japan. This research focuses on the effects of the municipal referendum on municipal amalgamation in Japan. Then, this research inquiries into the history and purpose of municipal amalgamation in Japan, the role of the municipal referendum, and the effort of the municipal referendum on the process of municipal amalgamation in Japan. Through the decentralization reform, Japan hopes top-down political system transit to bottom-up political system. But it is not easy. Even on the process of municipal amalgamation, it can observe the shadow of the centralization. Similarly, it also can observe that municipal referendum does influence the decision-making of municipal amalgamation. However, the meaning of the publicity is more important than the substantial result in this case. The implement of municipal referendum is advancing the democratic consolidation slowly but authentically. The spirits and experiences of Japan are worth to learn, especially in Taiwan, which faces the glocalization.