Introduction: This article presents some of the more important results from a study focused on the analysis of self-efficacy in written composition among deaf and hearing students. This type of self-efficacy is essential to adequate development of the complex process of writing and the quality of written texts. Method: A total of 116 students participated in the study: 25 from primary education and 91 from secondary education; 15 were deaf students and 101 had normal hearing. We administered an adapted scale on self-efficacy in writing, consisting of ten items on a 5 point-scale. This was followed by a comparison of motivational skills according to educational level and status of "deaf/hearing". Results: In general terms, it was found that deaf and hearing students in Primary and Secondary Education had developed a positive perception on their efficacy in writing. Nonetheless, important clarifications are called for, due to the variability in answers among the different scale items and among different students. Discussion and Conclusion: Due to a lack of studies of this type, we must insist on the need to carry out research that analyzes the affective components of deaf students' writing and that takes individual and contextual factors into account. (Contains 7 tables.)