The paper discussed the thing that clinical case diagnosis used in medical laboratory science instruction.In teaching,re-programmed the content section of course,re-planed the teaching procedure,they also directed students to select the cases and samples from sickroom,discussed and cariled out the diagnostic conclusion after laboratory teat.Thus,they could deal with the specific clinical issue perfectly.It was developed in the ability of clinical thinking,communicate between the students,teachers and patients,and the cooperation between students with the training mentioned and evaluation.