Abstract: Objective To compare bond strengh of 3M Transbond MIP primer＋3 M Transbond PLUS discolor light curing adhesive and GC Ortho LC light-cured resin-reinforced glass ionomer. Methods The study consisted of 80 maxillary premolars which were extracted for orthodontic treatment.The teeth were randomly divided into 8 groups, with 10 specimens in each.The specimens were bonded with brackets with the two bonding systems under the conditions of dryness, water pollution, saliva contamination and blood contamination respecitively. The shear bond strengh of each tooth was done with electronic universal testing machine, and the ARI scores were used to evaluate the residual adhesive on surfaces of teeth in each group under the microscope. Results In the shear bond strength test, comparing the first group with the fifth group, the second group with the sixth group, the third group with the seventh group, P＞0.01,there was no statistically significant difference; comparing the fourth group with the eighth group, P＜0.01, there was statistically significant difference. The results of ARI showed that there was no statistically significant difference in average ARI scores between the two bonding systems under the conditions of dryness, water pollution,and saliva contamination, but under blood contamination, the ARI score of GC Ortho LC decreased significantly. Conclusion Under the conditions of dryness, water pollution, and saliva contamination, the shear bond strength of 3M Transbond MIP primer＋3 M Transbond PLUS discolor light curing adhesive and GC Ortho LC show no significant difference, but under blood contamination, we recommend using 3M Transbond MIP primer＋3 M Transbond PLUS discolor light curing adhesive.