This research aims to determine the effect of self confidence on student’s mathematical problem solving abilities. The population in this research was all seventh grade students of SMP Swadhipa 1 Natar in the odd semester of the 2021/2022 academic year which were distributed in three classes, namely grades VIIA, VIIB and VIIC. The samples of this research were students of class VIIB and class VIIC who were selected by cluster random sampling technique with a total of 50 students. Research data taken in the form of quantitative data obtained from self-confidence questionnaires and tests of student’s mathematical problem solving abilities. Based on the results of hypothesis testing using linear regression analysis and correlation coefficient, it can be concluded that self-confidence has an effect on student’s mathematical problem solving abilities.