Negation as a modality has been interest scholars. At first, negation was described in the logical approach, but this description did not satisfie by linguists. As we know, Jespersen (1917) described it from a linguistic poini of view. I lis approach was developed by Klima (1964), Payne (1985), and Quirk el cri. (1985). In my thesis I try to describe the concept of negation in Javanese by referring to the concept which Payne has developed using a syntactic and semantic approach. The data collected for this thesis belong to the Ngoko variety of Javanese in magazines i.e. Jawa Anyar, Jaya Baya, Jaka Lot/hang, Alekar Seri, and l'wiyehar Semangal, further from the recording of a waywig kalif performance: Dewa Ruci. Being a Javanese native speaker. I have also included intuitive data. Negation in Javanese can De expressed syntactically by placing negative constituent in the sentence. The negative constituent can be a free or bounded form. The placement of the negative constiuent before the predicate, establishes standard negation. The negative constituent preceeding an adverbial forms a constituent- or special-negation. Negative constituents in Javanese can also form idiomatic expressions. Negation can be found in all types of sentence in the language. Syntactically, idiomatic expressions function as adverbials and semantically express modality. The negative marker ora 'not' underlies the derived affixed form, i.e. ngorakake 'say Not' which functions as a predicate and which semantically suggests the concept of denying ngiyakake 'say Yes'. Its derived form by reduplication, i.e. ora-ora functions as an adverbial and expresses the epistemic modality. Double negation causes the negative sentence to an affirmative one. Furthermore, double negative forms result in idiomatic expressions and syntactically function as adverbials. Semantically, it expresses the deontic modality.