Mathematics teaching theory is adapted from the teaching notes written and used by the author for many years, with unique ideas and a relatively complete theoretical system. Mathematics teaching theory discusses the quality of mathematics teachers, mathematics culture and mathematics education theory, and also studies some practical problems in middle school mathematics teaching. Mathematics teaching theory has collected many teaching cases and comments, which is helpful to improve the actual teaching level of mathematics teachers. Mathematics Teaching Theory is suitable as a teaching material for mathematics teaching theory and mathematics pedagogy courses for mathematics majors in normal universities, or as a reference material for postgraduate education and a teaching material for teachers' continuing education, and can also be used as a teaching material for mathematics education majors in self-taught examinations.