教會法在中世紀管轄權極廣，其內容不限於說教或道德的性質，且涵蓋人生的各種事務。教會法之支配力量始於公元400 年，在公元800 年至1200 年達到最高峰，又過了400 年後才結束，共12 世紀之久。何況教會法是大陸法系法律中，除了羅馬法外，第二古老的成份，正如羅馬法是世俗帝國的世界法一樣，教會法過去是精神世界的世界法。各個法律體系有有其適用的領域，且各有一套法庭、法官、律師、法典以及解釋的機制。教會法不但對以羅馬天主教為國教的國家的法制影響重大，而且大部分教會法還在英國實施直到19 世紀。即使時至今日，教會法對好多大陸法系與英美法系國家，包括我國的現行法制之發展，仍有極深遠的影響。為了對現行法制有更深的了解，實有探究教會法的必要。由於國內介紹教會法全貌之論著尚付闕如，本文試就教會法之起源、歷史演變、法源、內容以及對後世法制之影響與貢獻等問題加以剖析，以期填補此種真空。

The canon law of the Roman Catholic Church is the second oldest component
of the civil law system apart from Roman law. This body of law and procedure was developed by the Church for its own governance and to regulate the rights and obligations of its communicants. While the canon law was the universal law of the spiritual domain directly associated with the authority of the pope, in the Middle Ages before the Reformation, ecclesiastical courts had very wide jurisdiction particularly in family law and succession matters, as well as certain types of crimes. Its sway was at the zenith in the centuries A.D. 800-1200；it ended by four hundred years later, and it had begun four hundred years earlier beingtwelve centuries in all. Canon law has had a profound influence on the laws of European countries includingE ngland. The purpose of this article is to explore the origin, evolution , main features as well as its influence or contribution to modern laws.