The Number sense can vary in each individual, variations in number sense can be caused by mathematical learning experience, mathematical ability, and cognitive style. This research is a qualitative descriptive study that aims to find out the number sense profile of fifth-grade elementary school students in terms of the field-dependent and field-independent cognitive styles on fraction material. So the research began by providing a test of mathematical ability, cognitive style tests, and number sense tests. The research subjects involved two students of class V SDN Ngagel Rejo V Surabaya with field-dependent and field-independent style with equal mathematical abilities. Data collection was continued using the number sense test, and interviews, as well as checking using time triangulation. The results show that students with a field-independent cognitive style tend to use logical reasoning and actively process information and are able to simplify complex problems well. For example, when comparing the concept of numbers, they can show that there are other fractions or decimals between two fractions or decimals, while students with a field-dependent cognitive style only compare the values ​​of these two fractions or decimals, which means they have difficulty separating and distinguishing simple objects from complex object. Therefore, the cognitive style of students must be learned and harmonized with teaching strategies that exist in several schools. The adjustment of teaching in line with the cognitive style of students is needed to be able to bring about an increase in student performance.