Undergraduate thesis teaching is the "last line of defense" to guarantee undergraduate teaching quality. It plays an important role in promoting students' innovative and practical ability by cultivate their ability to analyze and solve problems with professional knowledge. Taking the practical teaching of undergraduate thesis writing in pharmaceutical majors as an example, the authors integrate Team teaching method and PDCA cycle method into various stages of graduation thesis including subject selection, experiment preparation, experiment implementation, thesis writing and thesis defense. As a result, the level of graduation thesis and the comprehensive quality of students are greatly improved.