Objective To compare two spray administration of intranasal dexmedetomidine (DEX) doses for premedication in children. Methods In this prospective,randomized,double-blind study,41 children aged 3-6 years were enrolled. Children were assigned to receive either spray administration of intranasal DEX 1 μg/kg (Group D1) or 2 μg/kg (Group D2). The Ramsay Sedation Scale scores were evaluated at 5 min intervals. Sedation status at separation from patient was also evaluated. Heart rate (HR) and saturation of peripheral oxygen (SpO2) were recorded before and every 15 min after drug administration. Results The median sedation onset time was 30 min and 20 min in group D1 and group D2,respectively. Compared with the children in group D1,those in group D2 were significantly more sedated when they were separated from their parents (61.9% vs. 95.0%,respectively)(χ2=5.549,P=0.010). In Group D2,the HR decreased by 15.8% (t=2.415,P=0.021) 30 min after the spray administration of intranasal DEX. Compared with the baseline values,there was no significant difference in both groups in terms of SpO2(t=-1.426,P=0.162;t=-1.096,P=0.280)and HR in group D1 (t=-0.299,P=0.767) 30 min after the spray administration of intranasal DEX. Conclusion Spray administration of intranasal DEX 2 μg/kg provides superior sedation in children.