This study is here to present the results of the analysis of students’ thinking processes in solving mathematical conceptual understanding’s problems based on visualizer and verbalizer cognitive style. This study is a descriptive study with qualitative approach. The instrument used in this study were conceptual understanding test, questionnaires, and interview sheets. With the snowball sampling technique, 7 students were selected for in-depth analysis of their thinking processes. The results of the analysis show that subjects with visualizer cognitive style solve the conceptual understanding problems by writing structured plans on the answer sheet and writing information in the form of image representations. On subjects with verbalizer cognitive style, they write answer plans in their own language and write information that is known systematically and in detail. Moreover, students with visualizer cognitive style get a lot of information from the pictures given in the problem, while students with verbalizer cognitive style tend to write (verbally) information on the questions.