The aim of the thesis is to study the negation in Muslim Baghdad Arabic variety. Iraqi Arabic variety has several different varieties because of the different ethnicities and religions in Iraq therefore the scope of the thesis has been limited to investigate just one type of Baghdad Arabic variety which is Muslim Baghdad Arabic (MBA). I used text analysis as a method in order to investigate the negation (system) in Muslim Baghdad Arabic variety. The material used was a book by McCarthy (1965) ‘Spoken Arabic of Baghdad, Anthology of text’. I also used Abu-Haidar’s article ‘Negation in Iraqi Arabic’ which is the most relevant work to my thesis as a starting point and for comparison with my discussion. The thesis has presented three different types of results. (i) There were some similar results that have been presented in both my thesis and the previous studies. (ii) There were some different results about some matters between my thesis and the previous studies. (iii) There were some new results in this thesis that have not been presented in any other studies.