Abstract: Medical informatics is a cross and practical course in information science and medical science.It is also an important professional basic course for biomedical engineering undergraduate students.This course includes lots of comprehensive and practical contents,and with the fast development of information technology,excellent textbooks are in short.Besides,due to lacking of practical experience,it is difficult for students to master the teaching contents,so the teaching content is difficult to master.Aiming at the existed common problems in the teaching of the course,this paper puts forward to a challenging experiment which guides students to design a practical hospital registration information subsystem.The goal of the design and the implementation of the experiment are described.Four years of teaching practice shows that,this challenging comprehensive experiment can stimulate students interest,in learning,enhance their practical ability,and achieve good teaching results.