Abstract： Objective To compare the feasibility of direct spinal puncture and reserving micro-catheter in spinal space during repeated intrathecal administration. Methods Forty Sprague-Dawley rats were randomly divided into 2 groups:direct spinal puncture (group puncture) and reserving micro-catheter in spinal space group (group reserve). The duration of operation were recorded. 5 days after operation, rata in both groups were intrathecally administerde morphine(10 μg/10μl) for 7 days and thermal withdrawal latency(TWL) were assessed. Results The operation in group reserve took shorter time than the group puncture, but micro-catheter were pulled out in 5 rats in group reserve. There is no difference of TWL between two groups. Conclusion Both methods are suitable for repeated intrathecal administration.