Ghada Abdel Aziz Mahmoud*,Mohammed E. Grawish**,MarwaSamehShamaa***,   Yasser LotfyAbdelnaby**** ^{*BDS,Dentist, Ministry of Health, Egypt **Professor, Department of Oral Biology, Faculty of Dentistry, Mansoura University, Egypt **Department of Oral Biology, Faculty of Oral and Dental Medicine, Delta University for Science and Technology, Gamasa, Mansoura, Egypt ***Lecturer, Department of Orthodontics, Faculty of Dentistry, Mansoura University, Egypt ****Professor, Department of Orthodontics, Faculty of Dentistry, Mansoura University, Egypt} Abstract: The aim of the study: was to evaluate the influence of deproteinizationby using NaOClon the shear bond strength (SBS) of metallic orthodontic bracket bonded using self-etching primer (SEP). Twenty two teeth were divided equally in to two groups (n=11). The facial surface of group 1 was left untreated. The facial surface of group 2 was exposed to NaOCl. The two groups were bonded to the facial surface using Transbond XT PlusSEP and Transbond XTadhesive. After bonding,twenty teeth from both groups were subjected to test the shear bond strength.Two teeth from both group were used to test the degree of bonding using scanning electron microscope (SEM). For two group comparison t-test was used. There was a significant difference between the two groups(P<0.05).NaOCl improve the SBS of Transbond plus SEP and Transbond XT adhesive. Keywords Deproteinization, sodium hypochlorite, shears bond strength, self-etch primer.