本文嘗試以三家《詩》輯佚史的脈絡，來討論王先謙《詩三家義集疏》一書的定位。 回顧先謙之前的輯佚歷史，由最初的直引法，演進而有師承法、推臆法，陳喬樅《三家詩遺說攷》將此三法充分發揮，而先謙全然承之，並以刪去法補充其中未辨家數者，使多數佚說皆有所屬。然而，此一現象雖看似輯佚法的統整與進展，但其中家數之鑑別，仍有許多未解之疑，先謙實未能深入探求，故其在輯佚上的貢獻，著實有限，顯然不若其書所集眾釋成果為佳。此外，是書論三家同異之處，體例不一，或謂三家說不能悉合，或又謂三家無異義，或三家之說當同，且多未經考查，可見其謹嚴不足。 先謙承魏源與馮登府之脈絡，輯三家佚說，集眾人釋義，肯定三家，批評《毛詩》，實乃一順理成章之勢。唯先謙對《毛詩》與古文經學之看法，實應分開看待，不應混淆，此點關係先謙看待今古文經之爭的態度，頗值留意。

This paper tries to discuss the positioning of Wang Xianqian's 王先謙 Shi Sanjiayi Jishu 詩三家義集疏 by tracing the history of the collection and compilation of the lost writings of the Three Schools of Poetry (Sanjiashi Jiyi 三家詩輯佚). The methods of Jiyi before Wang developed from quotation to teacher-succession and inference and deduction, and then Chen Qiaozon's 陳橋樅 Sanjiashi Yishuo Kao 三家詩遺說攷 brought them into full play. Wang succeeded all these methods and added the method of deletion to complement those unknown data, and make most of the lost writings belong to their right categories. However, Wang's discrimination to the classification of the lost writings was not deep and accurate, there were still much questions in it. Wang's contribution to Jiyi was limited. It was obviously incomparable to his book, which attained its achievements in gathering other people's interpretations. Moreover, the format of his book in criticizing the differences of the Three Schools was not coherent, it sometimes said that the opinions of the Three Schools were not all the same, sometime said that they had no differences, and sometimes said that they should be the same. Most of these criticisms were not well examined. It is thus evident that his book was not careful and precise enough. Xianqian's succeeding to the trace of Wei Yuan 魏源 and Feng Dengfu 馮登府 to collect and compile the lost writings of the Three Schools, gather other people's interpretations, approve the Three Schools and disparage the Mao School 毛詩 is a natural trend, yet, his viewpoints to Mao School and Confucian Classics in ancient texts 古文經學 should be treated separately and can not be confused. It is related to Xianqian's attitude to the disputation between Confucian Classics in modern and ancient texts, and thus is worth paying attention to it.