Students low confidence and learning achievement were as the background of this research. To improve students' confidence and learning achievement on angle measurement material, researchers applied the ARIAS learning model. This was a classroom action research with research subjects in grade IV B at SD Negeri 2 Karangsentul in Padamara district, Purbalingga with 21 students consisting of 9 male and 12 female students. Data collecting instrument on learning achievement used written tests in the form of evaluation sheets and confidence by using non-tests in the form of observation sheets and questionnaires. Data collection techniques used tests in the form of written questions and non-tests in the form of observation, documentation, and questionnaires. The results demonstrated that: (1) the percentage of students' learning achievement improved from the percentage of cycle I by 35% with low criteria to the percentage of cycle II by 78% with good criteria. There was an increase in learning achievement by 43%. (2) The students' self-confidence had improved from the percentage of the first cycle by 46% with sufficient criteria to second cycle by 75% with good criteria. There was an improvement in self-confidence by 29%. Based on the results obtained from the study, it could be concluded that the ARIAS learning model was able to improve students' self-confidence and learning achievement on the material of angle measurement in class IV B SD Negeri 2 Karangsentul.