Genre analysis has been widely used as an integrated approach in analyzing discipline-specific discourses in recent years. Profound studies have been carried out in the exploration of genre theories and genre-based teaching practices. Through a third-round experiment on the teaching of academic writing for postgraduates, the author of this research found it fruitful to incorporate a genre –based approach in the instructing process of the students’ academic writing classroom. In this study, a three-step framework of teaching, namely, modeling, joint negotiation of text and independent construction of text was carried out in the teaching process, in the course of which the teacher acted as a guide or negotiator together with the learners. More negotiation and more interaction between the learners and the products learners produced would simultaneously be fostered. Thus a critical genre analysis would rather be needed to enhance the learners’ social and cultural awareness of the texts they are supposed to produce. Such an ethnographic strategy could build learners’ perfect understanding and manipulating of the intertextuality and interdiscursivity of their academic discourses they are learning.