This research aims to describe mathematical representation abilities of Class VIII students in the implementation of the CORE learning model assisted by Canva which are reviewed from self-efficacy. The research subjects were students in class VIII C and VIII B of SMP Hasanuddin 5 Semarang. The data source in this research is students, obtained from tests result on students' mathematical representation abilities, self-efficacy dimension questionnaires, and interview. The research results show that there is a positive influence on self-efficacy on mathematical representation abilities, participants' mathematical representation abilities Students in terms of self-efficacy vary, in low, medium, and high categories. Subject with low self-efficacy were 5 (25%), subjects with moderate self-efficacy are 10 (50%), and subjects with self efficacy are 5 (25%).