In pediatric dentistry general anesthesia was recommend after all behavioral management method are failed. Stress, fear and fasting of child during operation can cause change in blood glucose level and sever blood glucose change can cause apnea, syncope and delay in recovery. This study design by randomized non - blind clinical trial and the aim of this study is determine and compare blood glucose change, before operation and anesthesia induction, after anesthesia induction and trachea intubation, after operation and before hospital discharge with intravenous anesthesia by Propofol and inhalation anesthesia by Isofluran in children between 4-6 years old refer to dentistry hospital branch of Isfahan medical University. Children are select for study when in complete health statement and haven’t any surgery operation past year and contraindication for Propofol and Isofluran use. Then parental consent and preoperative fasting instruction is obtained at the same. After refer, children are reassessment for general health and if they haven’t any surgery prevention, the cloths are changed and are sent to operation room. Children are select randomly for Propofol and Isofluran anesthesia groups, then if child haven’t any problem IV line is done, unless they are sedated with 50% N2O, 50% O2 and 5% Isofluran and when they don’t response to vocal irritants IV line done. Anesthesia induction in Isofluran group is achieved with Sodium thiopental 6mg/kg, Fentanyl 1µg/kg and Atracurium 0.8mg/kg, in Propofol group is performed with Propofol 2.5-3.5 mg/kg, Fentanyl 1µg/kg and Atracurium 0.8mg/kg. Anesthesia maintenance in Isofluran group is performed with 50% N2O, 50% O2 and 1.5% Isofluran and in Propofol group is achieved with 50% N2O, 50% O2 and 9mg/kg/hr Propofol. After finger disinfection blood glucose assessment is perform with drop of blood by glucometer (Accu-chek), before operation and anesthesia induction, after anesthesia induction and trachea intubation, after operation and before hospital discharge.