Objective To explore the practice effect of problem-based learning(PBL) in teaching of pathogen biology and immunology at college level.Methods Three-year clinical majors of class 1 and 2 in Luohe Medical College were chose,class 1 as PBL experimental group(n=100) and class 2 as control group(n=100).Chapter of hepatitis virus was taught respectively using PBL and LBL teaching method.Teaching effect was evaluated by test and questionnaire.Teaching effects between PBL and LBL were compared.SPSS 13.0 was used to do statistical analysis and data were expressed as percentage.Chi-square test was performed and P＜0.05 shows statistically significant differences.Results Results of test showed that excellent and passing rates were higher in PBL group than in LBL group(P=0.000) ; flunked rate was lower in PBL group than in LBL group(P=0.000).Results of questionnaire showed that more than 80％ students thought that PBL can mobilize students' initiatives of learning,train cooperation consciousness and enhance language skills,etc.Conclusions PBL can be used in pathogen biology and immunology for 3-year clinical majors and deserves further application.