Objective To explore the correlation between dose, blood concentration and efficacy of voriconazole in the treatment of invasive fungal infection in children. Methods 68 children treated with voriconazole during January 2019 to December 2019 were collected. The plasma concentration of voriconazole was assayed by high performance liquid chromatography (HPLC). The correlation between blood concentration and clinical efficacy was statistically analyzed. Results Different drug blood concentrations were obtained with different dosages: <4.0 mg/kg (6 cases) with the trough concentration ranged from 0.4 to 3.31 μg/ml (r=0.613, P=0.195). (4.0 - 7.0) mg/kg (44 cases), ranged from 0.35 to 7.02 μg/ml (r=0.325, P=0.018); >7.0 mg/kg (18 cases), ranged from 1.46 to 12.45 μg/ml (r=0.584，P＜0.023). There was a difference between the three groups (F=7.270, P=0.026). The relationship between the drug blood concentration and the therapeutic effect was obvious. In the <1.0 μg/ml group of 14 cases, 10 cases (71.4%) were effective, and 4 cases were ineffective. In the 1.0 - 5.5 μg/ml group of 48 cases, 44 cases (91.7%) were effective, and 4 cases were ineffective. In the >5.5 μg/ml group of 6 cases, 4 cases (66.7%) were effective and 2 cases ineffective. The difference among the three groups was obvious (χ²=5.360, P=0.039). Among the 68 cases, 58 cases (85.3%) were effective, and 10 cases (14.7%) were ineffective. Adverse reactions occurred in 10 cases (14.7%) with mild liver function injury, which did not affect the treatment and recovered with liver protection treatment. Conclusion This study showed that voriconazole was generally safe and effective in the treatment of invasive fungal infections in children. There was a significant dose-blood concentration and efficacy correlation. Further studies on pharmacokinetics and efficacy should be carried out to optimize the individualized treatment.