The study aimed to identify the relationship between cognitive dissonance and personality traits for students at Sultan Qaboos University in the Governorate of Muscat. The sample of study consisted of (263) students, which included (105) male, and (158) female students. The researcher was use descriptive method using the cognitive dissonance scale (Chow & Cassel, 2000), and (Shawkat, 2016), and the list of the five big factors of personality (Costa & McCrae, 1992). The results revealed the existence of cognitive dissonance, and there were no significance differences due to gender and academic year of the cognitive dissonance level. Also, the results revealed that there were no significance differences in the average degrees of personality traits factors between the individuals sample according to the academic year. Moreover, the study revealed that cognitive dissonance could be predicted through personality traits factors of extraversion, agreeableness, conscientiousness.