Within the scope of this study, a psychoeducation program based on multicultural competencies and Berry's acculturation model was developed to improve the adjustment process of international students. In this study, an explanatory sequential design was used. The study group consisted of 34 international students who volunteered for the study. The quantitative results of the study indicated that the Culture-Based Adjustment Program significantly affected the personal and social adjustment of international students. However, it did not significantly affect the adjustment to the university environment, emotional adjustment, dating relationships, and academic adjustment. The qualitative analysis yielded five major categories: (a) expectations, (b) contributions, (c) evaluation of the program, (d) leader, and (e) suggestions. The findings of this study highlight the importance of psychoeducation programs in the adjustment process of international students.