Background: Our previous work has shown a correlation between lower vitamin D levels in children with cancer and adverse prognosis. It suggests that supplying vitamin D is reasonable. VDR expression in childhood solid tumors has been linked to tumor characteristics and patient survival in only a few studies. Methods: For this study, 177 children with solid tumors were selected whose biopsies and tumor tissue formalin-fixed, paraffin-embedded tissue blocks were available for immunohistochemical analysis at Semmelweis University, Budapest (Hungary). Results: We found that non-significant VDR expression was associated with a significantly less favorable prognosis (p = 0.0061) in the examined childhood solid tumors. There was a clinically significant association; non-significant VDR expression had more than 14-fold odds of an unfavorable prognosis (OR = 14.74). The rate of VDR expression differed significantly between tumor types (p < 0.0001). Conclusion: In conclusion, VDR expression measured by IHC staining is inversely associated with aggressive characteristics in different childhood cancers. The downregulation of VDR expression in more aggressive childhood cancers suggests that functional vitamin D activity may slow or block cancer progression.