Abstract: Knowledge modeling method is helpful to separate out big concepts, divide and organize unit contents, which is a tool for unit overall teaching design. Applying knowledge modeling method, according to the reverse teaching design process, the whole teaching unit design of “the area of plane graphics” is carried out by integrating the contents related to the area of primary school mathematics with the big concept. For the students of Class 3, Grade 6, Primary School Y, X City, the teaching is divided into four periods. The post-test of experimental class and the comparison with the post-test of control class show that the students’ learning ability has improved, and they have a deeper understanding of perimeter and area, area units, and conversion methods. Finally, the application of knowledge modeling method in unit integrated teaching design is proposed in this paper.