Through the problem-based flipped classroom to solve the problems existing in the traditional urban planning principles course. The teaching contents of the course of urban planning principles are various and complicated. And the traditional teaching method is mainly based on teacher's narration, which leads to students' passive learning and poor teaching effect. In combination with PBL's flipped classroom, the traditional classroom will be flipped with the guidance of questions, forming a student-centered and teacher-directed ability training teaching. This paper introduces the concrete teaching practice plan, the practice includes modularized reconstruction of teaching content based on flipped classroom, and building learning platform on WeChat Subscription. It also clarifies the specific methods and steps of PBL flipped classroom before, during and after class, as well as the way of examination and evaluation. Through practical research, it is concluded that the teaching of PBL flipped classroom makes teachers more clearly understand the weak links of students' curriculum learning. Students' abilities in autonomous learning, communication and cooperation, summary and induction, and language expression have been greatly improved, and the teaching effect is improved.