In the history of mathematics education, different opinions as to how to view the phenomenon of mathematics education have been suggested in various ways. As those conflicting opinions have caused fundamental tensions in the phenomenon of mathematics education, they remain fundamental standpoints that have been continuously advocated until now - not limited in a certain period. It can be argued that this situation was caused by partial or fragmentary understanding of the phenomenon of mathematics education. If we are pursuing not a partial knowledge but a complete understanding of mathematics education, how should it be formed to comprehensively study the entire phenomenon of mathematics education? To answer this question, Complex structure in phenomenon of Mathematics Education can be proposed. It is an explanation for the opposing opinions existing in the phenomenon of mathematics education. The purpose of this paper is to understand the phenomenon of mathematics education as a whole.