This study aims to determine students' mathematical solving abilities using polya stages in sequences and series material. This type of research uses qualitative research with the sample used is 6 students who have high, medium, and low mathematical abilities. Samples were taken randomly from a class X consisting of 35 students. The data collection used was a written test on sequences and series material, and interviews with 6 students. The results of this study are students who have high problem-solving abilities can solve problems using polya stages completely and sequentially, students with moderate problem-solving abilities can solve problems completely and sequentially, but there is a mistake in solving so that it is repeated. Meanwhile, students with low problem-solving abilities in solving problems do not do one final stage. From these results, it is hoped that the teacher will provide more explanation regarding the material.