Background and purpose: Satisfaction with marital life is the most important issue in the joint life, which has the greatest effect on durability and failure of couple’s lives. Based on this, the main goal of the present research is to study the effectiveness of teaching intervention based on internal locus of control in increasing marital adjustment and satisfaction has been investigated. Materials and Methods: The research design was pre- and post-test with control group. Statistical population of this research includes 100 married students of Farhangian University of Babol, Iran. To determine the sample, initially 100 questionnaires of Rotter’s locus of control and Spanier’s marital adjustment were distributed among the married students. Among this population, 42 couples both had external locus of control and suffered marital maladjustment, 20 couples were selected by simple randomized method and were placed into two experimental and control groups, such that 10 couples were placed in the experimental group and 10 couples were placed in control group. Data were analyzed using the independent t-test method. Results: Research results showed that, since effectiveness of training communicational skills based on internal locus of control on increasing marital attachment of couples was calculated t-value (t = 6.04) and (t= 4.71) for women and men, respectively with degree of freedom of 19 is bigger than t-value in the table (t = 2.53) therefore, null hypothesis is rejected and with confidence degree of 99%. Conclusion: Teaching intervention based on internal control can be used as one of the intervention models for couples who suffer from marital dissatisfaction and think of divorce.