This study examined preservice teachers' culturally responsive literacy teaching self-efficacy changes during the field experiences in relation to the sources of self-efficacy. I delved into the meanings under the theoretical frameworks of culturally responsive teaching and social cognitive theory. I explored 84 preservice teachers' experiences over three semesters, who have been working with K-5 students from diverse backgrounds. Mixed-methods explanatory sequential design was adopted. In the quantitative phase, I administered a culturally responsive teaching self-efficacy survey before and after the field experiences. Additionally, sources of self-efficacy were studied using a source of self-efficacy inventory scale. Results of the quantitative study indicated that four different types of clusters exist: self-efficacy increased, self-efficacy high-stable, self-efficacy decreased, self-efficacy low-stable. In the qualitative phase, I investigated one preservice teacher from each cluster. This phase shed light on the reasons for the different self-efficacy change patterns among the preservice teachers. Findings from both phases (quantitative, qualitative) have implications: 1. It is crucial for both teacher educators and preservice teachers to understand their culturally responsive teaching self-efficacy and its changes. 2. Culturally responsive teaching self-efficacy and the sources of self-efficacy display reciprocal interaction. An awareness is critical of how preservice literacy teachers' experiences in the field affects their culturally responsive teaching self-efficacy and other sources of self-efficacy. In light of the findings of the current study, teacher educators may wish to consider helping preservice teachers form informed and realistic culturally responsive teaching self-efficacy. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]