Objective To evaluate the effect of case-based learning combined with standardized patients in probation of nuclear radionuclide therapy.Methods 360 interns were randomly assigned separately into CBL+SP group and LBL group (180 people),case based on SP as the center of clinical teaching mode was used for CBL+SP group,while traditional classroom teaching mode was used for LBL group.Theoretical test,case analysis and teaching satisfaction survey were used to evaluate the two teaching mode,using SPSS 20.0 software for statistical analysis of the data.t test was used for two independent samples of both theoretical test and case analysis and chi-square test was used for teaching satisfaction survey.Results The score of theory and case analysis of CBL+SP group was higher than that of LBL group,and the difference had statistical significance [(83.26 ± 4.18) vs.(80.36 ± 3.62),t=-7.041,P=0.000;(85.79 ± 4.15) vs.(81.26 ± 3.96),t=-10.844,P=0.000].Satisfaction survey showed that satisfaction degree of CBL+SP group in stimulating and training the correct clinical thinking,grasping the information skills and cultivating their ability to analyze and solve the problem was higher than that of LBL group,and the difference had statistical significance (x2=40.319,x2=33.620,x2=23.493,x2=23.283;P=0.000).Conclusion Case-based learning combined with standardized patients in probation of nuclear radionuclide therapy can obtain satisfactory teaching effort.