This research aims at offering a comparative analysis of the “negative sentence” in the Semitic languages, Akkadian, Hebrew, Ugaritic and Arabic. The research proceeds from the linguistic use in Hamorabi's legislations, The Genesis, The Holy Quran, and The myth of Aqhat. The method used was examining these texts, following up the cases of agreement and disagreement in the syntactical functions of the negative particles. I tried in to clarify the effect of these particles in the time-meaning of the syntactical structure through the negative case of the nominal sentence, verbal sentence, and absolute negative. Then I presented the features of NOT, the oldest negative particle in these languages. This examination allowed the research to survey the cases of the negative sentence in the light of order and apocopation. It refers to the relation between exception and negative, negative and interrogation, negative and confirmation. It draws attention to the phonetic changes in the negative particles. As a conclusion the research states the linguistic study of the negative sentence is of the basic body of the language. It does not suffice to study the concept of the sentence as it is mentioned in the books of Arabic or Semitic syntax. The research proves that the comparative Semitic study endeavors to deep root the linguistic semantic study of the particles. It presents scientific explanation in phonetic, syntactical and morphological cases. The researcher is ushered to a wider space in the field of linguistic analysis of the structures in the Semitic sentence.