Professor Xu Guozhang, though publicly esteemed as a linguist and an English-teaching expert, quite often regarded himself as a philosopher of language. This paper first examines Xu’s guiding principles of linguistic research, i. e., Li (logic) and Tong (penetration) , based on which we then make a detailed analysis of Xu’s Philosophy of linguistics(PL)from an additional Zhe (dialectic)perspective. Lastly, we draw a contrast between Xu’s PL respectively with western philosophy of language as well as traditional Chinese philosophy of language. We conclude that (1) Xu’s PL, differing from western philosophy of language, can be justifiably classified under the scope of philosophy of science; （2）Xu has shown his speculative talent for pure philosophy in a couple of his works; （3）Xu‘s PL, characterized by three features, i. e., Li, Tong, Zhe, is quite ambitious and grand, and embodies the qualia and essence of traditional Chinese philosophy of language.