The problem of religious land use and illegal building disputes has existed for years and becomes a universal phenomenon in Taiwan. The violation of land-use regulations by religious groups is often exposed by construction of buildings without license, illegal occupation of public lands, disputes over the transfer of farmland ownership, and non-conformity for a given property between different titles used on property records and Temple Registry. Due to the incapability of religious groups to confront all controversies and find a solution, all these problems have become a thorny issue for the government in its management of religious affairs. Starting its research from legal angle and land vulnerability in Taiwan, this paper applies scoring technique and statistical analysis with in-depth interviews to analyze data collected from conversations with officials, scholars, and religious groups. Based on the theory of land development analysis, this research separates all questions in relation with unlicensed building and misuse of land into 18 categories, establishing a prioritized list in accordance with a weighted system, as a reference for problems solving. This paper suggests that the government should prove more lenient to provide a path to legalization for illegal land use and unlicensed buildings, but if problems involve vulnerability and sustainable development of land, public administrations should give them due consideration in their deliberations and take some countermeasures. Information provided in this paper is expected to serve as reference for future research and practical treatment.