This study aims to examine the impact of teaching problem-solving strategies conducted during math class, to students with mild intellectual disabilities on their success in problem-solving. One of the qualitative research methods, the teaching experiment, was used in this study. The participants' group of the study consists of three students from the high school group of special education who were selected by the criterion-sampling method, one of the purposeful sampling techniques. The teaching of intelligent guessing and testing, making a drawing (making a drawing shape, schema, and diagram), and working backwards strategy, all of which are from the problem-solving strategies, was performed using the direct instruction method in accordance with teaching experiment methodology. During the teaching process, eight problems were taught and solved, including 4 in each strategy course plan. In total, 24 problems relating to these three strategies were studied, and the implementation process lasted nine weeks. The research process was recorded via a video camera, and all recordings were transcribed and analyzed by thematic analysis. As a result, it has been concluded that the teaching of problem-solving strategies to students with mild intellectual disabilities improves their problem-solving skills and has an impact on the problem-solving process. In light of the findings and results, it is recommended to teach problem-solving strategies to students with mild intellectual disabilities to improve their problem-solving skills in math class.