Li Shu's ”Detailed Commentary on the Mao Poetry” is a collection of commentaries, and Huang Chun's ”Interpretation of the Classic of Poetry” a synthesis of treatises and commentaries. The two books are later integrated into ”Li and Huang's Collected Commentaries on the Mao Poetry”, which features extraordinary editing, narration, and elaboration. This book is significant in the history of ”Poetry” studies, because it reveals Sothern Song scholars' traditional interpretation of the ”Classic of Poetry” and their collections of and comments on Northern Song scholars' theories. Considering it has originally been two independent books, this study discusses Li's and Huang's elaborations of the ”Classic of Poetry” separately. Focused on Collected Commentaries's distinctive compilation genre and Detailed Commentary's and Interpretation's writing styles and interpreting methods, this study explores the books' features and compares them so as to find the internal reasons for the compilation. The result shows that ”Collected Commentaries” is designed with Li Shu as the lead author and Huang Chun as the co-author and yet Huang's elaboration with criticism and more meticulous and delicate interpreting methods is equally important. This study also proves that the Northern Song scholars that question the author and the content of the ”Preface to Classic of Poetry” do not exert strong influence until Zhu Xi completes the new edition of his ”Collection of Commentaries on the Classic of Poetry” and his followers promotes it zealously.