Abstract
Previously, tudung saji was studied as a subject in the field of ethnomathematics, and the tudung saji patterns were displayed on a triaxial template using a tumbling block. However, the tumbling block is limited in its use due to the complexity of its structure and the applicability of the analysis. Due to its complex structure, the planar transformation is discussed to facilitate mathematical analysis, especially on a triaxial template. To define the isomorphism theorem on the transformation between a tumbling block and a 2D normal square grid, some mathematical elements on the planar are analyzed. As aresult, the isomorphism theorem for the planar transformation is defined, and the triaxial template of tudung saji patterns is represented in the new template.