Spinal anesthesia has been safely and reliably performed in minor pediatric surgery. Preterm infants are more likely to develop respiratory or cardiovascular complications after general anesthesia than full tern infants. This regional anesthesia may offer special advantages for surgical procedures such as inguinal hernia repair in former premature infants with a history of apnea and bradycardia of prematurity. Spinal anesthesia was done in sixty seven infants and children under 15 years of age, who were to undergo minor abdominal and lower extremity orthopedic procedure. In all cases 0.25 mg/kg of 0.5% hyberbaric tetracaine was injected into subarachnoid space. Age-related 4 groups (0~1, 1~6, 6~12, 12~15 years-old) were divided. The depth of lumbar puncture, sensory block, hemodynamic changes, status of sedation, duration of anesthesia, complication following spinal anesthesia were observed. The results were as follows; 1) Lumbar puncture was successed in 66 cases(98.5%), but failed in 1 case(1.5%). 2) The highest correlation in depth of lumbar puncture was with body-surface area(y=1.19+2.06x, r=0.956, p<0.001). 3) The mean height of sensory block in all age-related groups was similar between T(5) to T(6) skin dermatome. 4) Chidren less than 6 years of age showed a little changes in blood pressure and heart rate following spinal anesthesia. But children more than 6 years of age had widely varible decreases in blood pressure and heart rate, and recieved ephedrine(4 cases) or atropine(2 cases). 6) 55 cases(82.1%) required sedation with midazolam or propofol, 8 cases(10.6%) required general anesthesia to complete operative procedure. 7) The time needed to regain motor funtion increased with age (y=1.04±O.llx, r=0.952, p<0.001). 8) Preoperative complications were bloody tap (5 cases), hypotension (14 cases), bradycardia (6 cases), nausea or vomiting (4 cases), insufficient analgesia (2 cases), and failed tap (1 case). Postoperative complication was nonspecific postdural puncture headache (1 case). From the above results, it was suggested that spinal anesthesia without use of potent inhalational anesthetics in minor pediatric surgery is one of useful method under meticulous monitoring and observation.