This paper deals with the work of Abdullah Ibn al-Mutazz,Kitab al-Badi'While there wee the challenges againts the reputation of Ibn al-Mu'tazz over his role on developing'ilm al badi on Arabic letters,this work shows that Abdullah Ibn al-Mutazz was deemed as the person whose contribution to the Arabic letters like ilm al-badi was unquestionable with regard to the study of Rhetoric and discourse on Arabic language,two mainstreams were commonly recognized, Arab and philosophy of logic deriv ed from Greek,and Ibn al-Mutaz was among the pioneers of Arab linguisticts.....