Objectives Micronutrient deficiencies (MD) are a public health concern in preschool children in many developing countries, including Belize. MD can impair proper growth, motor and cognitive development, and functioning in children. We assessed the prevalence of vitamin A deficiency (vitAD), anemia (AN), iron deficiency (ID), iron deficiency anemia (IDA), red blood cell folate deficiency (RBCFD), vitamin B12 deficiency (B12D), and marginal deficiency (B12MD) among preschool children (6–59 months of age). Methods We conducted a national multistage cluster probability household biomarker survey of 971 preschool children. Demographic characteristics and blood samples were collected and analyzed. We used BRINDA regression adjustments for ferritin and retinol to account for inflammation. Prevalence and 95% CI of vitAD, AN, ID, IDA, RBCFD, B12D and B12MD were estimated. Results The national adjusted prevalence estimates showed very low prevalence of vitAD (<22 mcg/L) 0.3% (95% CI: 0.0, 0.6). The national prevalence estimates for AN (hemoglobin < 11 µ/dL), ID (ferritin < 12µg/dL), IDA (ferritin<µg/dL), and RBCFD(<305 nmol/L) were: 20.1% (95%CI: 17.2, 23.3), 7.7% (95%CI: 5.9, 9.9), 19.9% (95% CI: 14.1, 27.2), and 33.5% (95% CI: 29.1, 38.3), respectively. The prevalences of B12D (<148pmol/L) and B12MD (148–221 pmol/L) were 6.1% (95% CI: 4.5, 8.1) and 12.8% (95% CI: 10.4, 15.7), respectively. Conclusions Our study revealed a low prevalence of vitAD, Vitamin A deficiency has been practically eliminated in belize. In contrast, ID, IDA, B12D and B12MD are of mild public health concern. In contrast AN and RBCFD are a moderate public health concernthat should be addressed in this age group. Funding Sources None.