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This study seeks to evaluate the SBRT dosimetric benefit of Cyberknife and TomoTherapy for spinal tumor patients, in regards to successful plan acceptance and lower dosage to critical structures. This study compared the 2 systems in dose volume histogram (DVH) quantitatively, by using several indices for the dosimetric comparisons, including the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV). We planned L3 (n = 2), L5 (n = 1), T12 (n = 1), C3 (n = 1), and T5 (n = 1) spinal tumor case with planning target volumes ranging from 3.55 ~ 17.95 cc. Prescription dose is 1600 ~ 2000 cGy per single fraction. Cyberknife prescribed 80 ~ 85% in PTV and Tomotherapy 90 ~ 95%. The dosimetric data were compared between the two treatment systems by calculating the CI, HI, and maximum doses to the OARs from the treatment plans, which are generated for each site. Regarding the the homogeneity of PTV, both plans gave satisfactory results and no significant difference was observed. The spinal cord satisfied the partial volume tolerance dose (volume 10%, dose 10 Gy) in 16 ~ 18 Gy single fraction. We found that both planning systems satisfied the required PTV prescription, but better dose conformity and dose homogeneity, but a poorer dose gradient were achieved with HT compared with CK.