宜蘭民間信仰承襲部分中國閩粵漢人風俗，其中無祀孤魂信仰源遠流長，在臺灣民間信仰中屬於陰廟系統，其廟祠數量龐大、分布廣泛。本文研究以田野調查之文獻分析、觀察、訪問以及對研究資料的歸納分析，試圖理解宜蘭溪南地區無祀孤魂信仰的類型與發展歷程，特別是升格現象在宜蘭溪南地區無祀孤魂廟祠所扮演的重要性；並藉由各項資料剖析該類廟祠在地理空間分布、建築空間與祭祀空間的特性，以期理解廟祠與周圍人群、社區與地理空間的關係。研究成果如下：其一，無祀孤魂廟祠在溪南地區種類繁多，部分廟祠翻修數次，藉由升格手段提升廟祠位階，使其神格提升；在蘇澳地區的12座城隍廟就是最好的例子。其二，在廟祠的地理空間分布上，鄰近水域空間的部分廟祠其骨骸來源與河川氾濫、海難背景相關；而鄰近墳塚區的廟祠其骨骸源自墳塚的可能性較高；此外，多數廟祠位於主要聚落邊緣或偏僻位置，顯示民眾對於陰廟的設置多採迴避策略。其三，就廟祠的建築空間分析，通常神格階層較高之廟祠，其建築規模較大，建築元素多元；另就座向分析，以座北朝南、座西朝東者最為普遍，此與周圍地理環境空間特性、聚落分布、墳塚座落位置等相關。其四，就城隍廟的普渡祭典的儀式進行與空間配置，理解人與人、人與鬼以及人與地的關係。

Yilan's has many folk religious traditions, inherited partially from social customs in China's Fujian and Guangdong provinces. One of which is the worship of wandering ghosts, which has a long history. Wandering ghost worship is considered as a system of Yin temples in folklore, Yin temples are numerous and widely distributed. The present study uses reference analysis of field investigation, observation, interviews, and inductive analysis of research materials to try to understand the type and development of wandering ghost worship in Yilan's Xi'nan area. Of particular interest is the importance of the promotion of the spiritual hierarchy of the ghost temples in this region. The study materials are used to analyze the characteristics of temples in terms of geographic spatial distribution, architectural space, and worship space to comprehend the relationships between temples and their surroundings, communities, and geographic space. The following are the conclusions formulated in this study. Firstly, there is a wide variety of wandering ghost temples in the Xi'nan area. By means of repeated renovation, some of the temples have upgraded their status as well as the spirits worshipped in them. The twelve Cheng-huang (City God) temples in the Su'ao area are excellent examples of this phenomenon. Secondly, with respect to these temples' geographic spatial distribution, the bones worshipped at temples located near bodies of water primarily came from victims of flooding or the fury of the sea. The bones worshipped at temples located near burial sites were likely to have come from the areas. Furthermore, the large numbers of temples situated at the edges of settlements or in remote locations show that ghost temples are shunned by the local people. Thirdly, the analysis of the architectural space of the temples shows those temples dedicated to spirits or deities with higher statuses tend to be larger and more intricate. The most common placement of temples are facing south and east. This is related to the surrounding geographic characteristics, the distribution of settlements, the location of burial sites and so on. Lastly, Ghost Festival rituals at City God temples are conducted and arranged with consideration for the relationships between man and man, man and ghost, and humans and the land.