This research is aimed at describing the ability of mathematical reasoning
of students of SMK Negeri 1 Banyumas (Public Vocational High School 1 of
Banyumas) viewed from the Mathematical Anxiety. This research used the
descriptive qualitative method. The subject of this research was a group of grade
X AK 3 (Accounting class) students. The purposive sampling technique was used
by taking three students in each of normal, slight, and medium Mathematical
Anxiety groups. The data were collected through questionnaires, test, and
interviews. The data were analyzed using data reduction, data
presentation/display, and data conclusion. The researcher gained the data
validation by the triangulation technique. The results show that in the normal
Mathematical Anxiety group, there are two students mastering the five reasoning
indicators and one student mastering the fifth indicator which is finding the
pattern to make generalization. Meanwhile, all students in the slight and medium
Mathematical Anxiety groups master the indicators of the ability to initiate
prediction, to do mathematical manipulation, and to arrange evidences.