Background: Previous studies have implicated the important and active role of vitamin D in the immune system. Objectives: The aim of this study was to evaluate serum levels of 25-hydroxyvitamin D in children with burn injuries. Materials and Methods: In this cross-sectional study, 118 patients with various degrees of burn injuries were enrolled. A checklist consisting of demographic data, total body surface area (TBSA) affected by burn, degree of burn, serum level of 25(OH)D, total protein, albumin, electrolytes, and parathyroid hormone was recorded for each patient. Results: Sixty-eight (57.6%) males and 50 (42.4%) females with a mean age of 4.04 years (SD = 3.04) were evaluated. The mean level of 25(OH) D was 14.58 ng/mL (SD = 6.94). Levels of 25(OH)D in four (3.39%) cases were higher than 30 ng/mL, while 95 (81.35%) cases had levels lower than 20 ng/mL, and 19 (16.10%) cases had levels of 21 - 30 ng/mL. The level of 25(OH)D was below recommended levels in 96.61% of cases, while 81.34% had vitamin D deficiency and 16.1% had insufficiency. We found a significant correlation between vitamin 25(OH)D and total protein, albumin, and total and ionized calcium (P < 0.001). There was also a significant negative correlation between 25(OH)D and TBSA affected by burn (P = 0.001). Conclusions: The levels of 25(OH)D in children suffering from severe burns were low. Supplementation might be useful in patients with very low levels of serum vitamin D.