The book “Al-Wasata” is one of the books that occupied an important place in the heritage of Arabic criticism. The issues which the book discusses drew the attention of researches who had growing interest in criticism standards. However, the techniques which “Al-Qadi Al-Jurjani” used to support his views, although important, did not receive enough attention from researchers. This study aims at acknowledging the most important persuasion techniques used in the book “Al-Wasata” and their relation to the subject of discourse. Keywords: Critic Heritage – New Rhetoric – Argumentation – Al-Qadi Al-Jurjani.