The dependency of the characteristics of 980nm high power vertical-cavity surface-emitting Lasers (VCSELs) on the distributed Bragg reflector (DBR) reflectivity was analyzed theoretically. The output characteristics of the VCSELs with different active region diameters were calculated. The output characteristics at different DBR reflectivities were analyzed. It is found that the variation of DBR reflectivity exerts different influences on the VCSELs with different diameters of active region. The test experiment was carried out in order to validate the theoretical analysis. The experimental results show that the output powers of VCSELs with 500-μm-diameter active region under the injected current of 6A are 2.01W and 2.09W when the N-DBR reflectivities are 99.7% and 99.2%, respectively. However, the output powers of VCSELs with 200-μm-diameter active region under the injected current of 3A are 0.64W and 1.12W when the N-DBR reflectivities are 99.7% and 99.2%, respectively. It was concluded that the theoretical results are validated by the experiment effectively.