The goal of the present research is to examine the relationship between locus of control and marital satisfaction of couples. The method of this research is descriptive one and of correlation kind. Statistical population includes the married students of Islamic Azad University of Sari. Research sample includes 62 couples who were selected by multi-step clustered sampling method. Research tools include locus of control (Rotter) and marital satisfaction (Enrich). Data was analyzed using of the methods of descriptive statistics and deductive statistics (The agreed correlation coefficient, X-2 square, and T-test). The findings showed that there is a significant relationship between internal locus of control and marital satisfaction of the couples. Also, results showed that there is no significant difference between the gender and the kind of locus of control, gender and level of marital satisfaction of the couples. Regarding the finding of the research, couples who suffer from decrease and dissatisfaction in marital relationship, have external locus of control, therefore, for improvement of marital relationship problems and having a coordinated, attractive and satisfactory marital relationship, it is suggested to replace internal control instead of external control. [Askari Asghari Ganji, Drshokouh Navabinezhad. The Relationship between Locus of Control and Marital Satisfaction of Couples. Life Sci J 2012;9(4):294-298]. (ISSN: 1097-8135). http://www.lifesciencesite.com. 43