張載是北宋諸儒中儒學理論體系最為完備的哲學家，其義理之學深受推重，而又以長於實踐禮教為特色，故其講學以更革學風、求為聖人為宗旨。本文著眼於其學術實踐的特色，以「知禮成性」說為中心，從禮的天道根源、禮的文本、禮的心性與人問倫理意涵，以及禮的實踐等四方面，遞進討論分析，以見其禮論如何與其哲學體系一體貫通，並實踐於日常之中，以凸顯張載學術兼重義理與實踐二端的特色。張載禮論的特點，在由天道論的太虛、太和境界，下貫到人間社會，賦予公共禮儀生活、人間的倫理秩序，乃至個人的生命存在，一個大公流行的自然理則。個人智性能「極其高」以體知天道理序，充分豁顯內在的天地之性；社會性身體能行禮以「著實處」；內外合一以共同創造「成性」之可能，這才是「真義理」。因此，合禮的生活，是即合於天道的生活。張載不僅在哲學理論上貫通天道與人道，更在推行禮制上勇於實踐與自作楷模，乃至化民成俗，是理學家在推動儒學復興的努力上，有具體成果的一人。

Zhang Zai's philosophy is perhaps the most complete exposition of Confucianism from the Northern Song. His theory of ethics which emphasizes the practice of etiquette and moral standard is highly valued, and the objectives of his teaching are the reorientation of scholarship and the personal attainment of sagehood. This study considers aspects of ritual practice, focusing on four aspects to his discourse of "zhi li cheng xing:" its origin in the Way of Heaven, its textual basis, its content in the individual mind and in human relations, as well its practical application in daily life. These four aspects are analyzed step by step to understand how his practical ritual theory and his theoretical philosophy are part of a consistent body of thinking and how he intended them to be put into practice. This demonstrates how Zhang Zai's philosophy has a dual focus in both ethics and practice.The main characteristic of his ritual theory is that the tai xu and tai he that make up his cosmology, giving a natural principal to human society in its three levels of public rituals, the order of human social relationships, and the meaning of individual life. The inner ability to comprehend cosmological order to the highest level enables the complete expression of the nature of Heaven and Earth, while the outer body can physically practice the rituals. This unity of inner and outer, together creates the possibility of bringing "human nature to completion." In his view, this is the true meaning of ethics. A life conforming to ritual will also be in accord with the Way of Heaven. This paper shows how Zhang Zai in his willingness to himself provides a model of actually practicing traditional ritual, and in the end he was able to alter human customs, which makes him a scholar whose work truly had animpact on society.