‘Muu Tan Ting'(also called ‘Hwan Hwen Ji') is the greatest drama work that has enormous impact on the Chinese drama world after 'Xi Xiang Ji', and it is also the best and proudest drama work of Tang Hsien–tsu in his life . Since it born, this drama has appealed so much enthusiastic discussing that almost all of the noted Chinese dramaturges have ever given their opinions to it in different ways, such as making a preface, postscript, comments, adaption, revisions, and so on. These zealous efforts make a large contribution to perfect the showing effect of this drama on the stage. Even the debate between contrary positions also provoked a lot of excellent theories and enriched the content of Chinese drama. Hence, we have good reasons for viewing ‘muu tan ting' as the most important work in the developmental history of Chinese drama. Tsang Mao-hsun revision of 'Hwan Hwen Ji' is just one of the adaption and commenting of this drama. This work didn't get much attention or looked upon by critics before, even with the notorious fame as 'the enemy of Tang Shean-Zu' which means it deteriorates the level of Tang Shean-Zu's work. However, I don't agree this opinion. Once examining of Tsang Mao-hsun 's achievements as a dramaturge, we will conclude that his work won't be valueless at all. As a researcher, I have looked for a lot of better copies of this work, compared and analyzed them with the original one, and finally found that he had given a lot of valuable opinions for ‘muu tan ting', such as the removing and combings of drama structure, the revising and commenting of drama plots and songs, the reduction and supplement of actors, the arrangement of settings, and the hint words for drama--all of them gave a mass of important contribution for the progress of Chinese drama. Therefore I expect to express it integrant ally by this article, and give fair comment for Tsang Mao-hsun 's revision of ‘Hwan Hwen Ji'.