Objective　To explore the methods and results of the application of formative as sessment in gynecology and obstetrics nursing teaching. Methods　In the gynecology and obstetrics nursing teaching practice，556 undergraduate students in Grade 2011 were set as experimental group while 339 students in Grade 2010 as control group. Based on the teaching syllabus， in the experimental group， traditional lecture and bilingual teaching method were applied in theory courses and PBL or PBL combined with Scene simulation were applied in practice lessons. And after the teaching， forma tive assessment was applied in the experimental group， which included setting up small study groups and learning files， giving evaluation to students' participation in class activities， written assignments， operation exams， attendance to classes and their in class test results. In the evaluation of a student， the results of formative assessment took a proportion of 50% and the final exam result took the other half. While in the control group， traditional summative assessment was applied， namely， results of the final exams were the terminal results of students. Results　Gynecology and obstetrics nursing got the first prize in the Final term Assessment of Teaching Efficiency of the Nursing School. When comparing the results of the final exam of the students in the experimental group and the control group， there was statistically difference（P=0.000）， and 86% of the students in the experimental group were in favor of formative assessment. Conclusion　When applied in gynecology and obstetrics nursing teaching in undergraduate students， formative assessment can help teachers adjust teaching methods to improve the effectiveness of teaching； it can also make students more motivated in learning and help students form good learning habits and improve their learning strategies， which can improve students' compre hensive quality.