The authors report the experience of twenty patients of transpedicular Zielke instrumentation after anatomical reduction of the spondylolisthesis. Anstomical reduction was done with the aid of temporary application of Harrington distraction rod, and the reduced segment was fixed with transpedicular Zielke instrumentation. And, anterior interbody fusion was supplemented in a single stage operation. Follow up period was between 13 to 25 months after operation with the average of 19 months. 1. The age of the patients was 38 years in average ranging from 11 to 61 years. 2. Types of the spondylolisthesis were spondylolytic type in 11 cases, degenerative type in 6 cases, dysplastic type in 1 case and pathologic type in 2 cases. 3. The level of the lesion were L5-Sl in 12 cases, L4-5 in 7 cases and L3-4 in 1 case. 4. Pre-operative clinical feature included low back pain in 95%, radiating pain in 65%, and neurological claudication in 45%. 5. The average percentage of slippage was changed from 24% preoperatively to 6% postoperatively and to 8% at the final follow up. The initial correction rate was 75% and the amount of correction loss during the follow up period was 11% in average. 6. Slip angle was changed from 3°preoperatively to −3°poetoperatively and to 0°at the end of follow up. In the 12 cases with local kyphosis, average slip angle of 14°preoperatively was improved to 2°postoperatively, and to 7°at the end of follow up. 7. Bony fusion was obtained in 19 cases within 4 to 6 months. 8. There were 2 cases of metal failure with considerable loss of reduction ; one patient with pathologic spondylolisthesie due to active tuberculous spondylitis required re-operation and another patient showed fusion eventually in the redisplaced position. Other complication included 1 transient dysuria, 1 ileus and 2 meralgia paresthetics. 9. Clinical symptoms were improved in 95%. Follow up result of the operation according to Gill's criteria were excellent 65%, good 25%, fair 5%, and poor 5%.