This study aims to improve students' mathematical problem solving skill at class VIII A of SMP Muhammadiyah Sokaraja using IKRAR learning model. Problem-solving skill includes 4 aspects, those are: skill to understand the problem, skill to plan the problem, skill to solve the problem, and skill to see again. It is a classroom action research conducted in 3 cycles with 2 meetings for each cycle. At the end of the cycle, students are given an evaluation test to measure the skill to solve mathematical problems. The instruments used in collecting data in the research are observation sheet and evaluation test. The results shows that IKRAR learning method improves mathematical problem solving skill for students with high ability, but it is not able to improve mathematical problem solving skill for students with low and medium ability. It is proven by the result of mathematical problem solving skill test showing the average score of each cycle; 51.11 (cycle 1), 73.05 (cycle II), 70.69 (cycle III). It is also found that average score of students with high ability improves from 78.25 (cycle II) to 78.75 (cycle III). While the average score of students with medium ability decreases from 71.58 (cycle II) to 64.16 (cycle III) and the average score of the students with low ability also decreases from 70.20 (cycle II) to 69.16 (cycle III).