Purpose: To investigate improvement in iron and iron-related nutritional status of children with severe-early childhood caries (S-ECC) following dental rehabilitation under general anesthesia (GA). Methods: Children with S-ECC were recruited into a prospective study investigating changes in nutritional status before and after surgery. Parents completed a questionnaire, as their child had a venipuncture while under GA. Children returned for follow-up at a minimum of three months postsurgery, and parents completed a follow-up questionnaire and their child had an additional venipuncture and dental examination. Statistical analyses included descriptive, bivariate, and multivariable regression analyses. Results: A total of 150 children participated (mean age 47.7±14.1 months). The mean baseline ferritin concentration was 27.9±19.1 μg/L, while mean iron and hemoglobin levels were 12.3±4.3 μmol/L and 107.5±9.2 g/L, respectively. Overall, 53 percent were anemic, 30 percent had iron deficiency (ID), and 20 percent had iron deficiency anemia (IDA) at baseline. In total, 106 participants returned for follow-up. Paired t-tests revealed significant improvements in ferritin (27.0±18.4 μg/L versus 34.3±18.2 μg/L, P<0.001) and hemoglobin (108.2±8.3 g/L versus 123.7±9.4 g/L, P<0.001) levels. There was a 16 percent reduction in children with ID (P<0.001) and a 20 percent reduction in children experiencing IDA (P=0.011) from baseline to follow-up. Multivariable regression revealed that follow-up ferritin levels were associated with baseline ferritin concentrations, red meat intake, and difficulty purchasing food because of cost. Conclusions: Improvements in iron and iron-related nutritional status were observed post GA. Dental surgery for S-ECC may contribute to improved children's eating practices and resolve oral inflammation, thus leading to better nutritional status.