Objective To discuss the technical keypoints of the second-phase diaplasis treatment after Hartmann operation. Methods Twenty-one cases of the second-phase diaplasis operation of Hartmann operation in this hospital from January 2003 to December 2007 were analysed retrospectively. Results In this group, stapler technique was used in 15 cases, anastomotic ring was used in 3 cases, and one-layer suture was used in 3 cases. The time of these operations was between 118 min and 240 min (mean 164 min). Neither stomal leak nor stomal stenosis occurred, acute ileus occurred in 2 cases, and both recovered after the treatments of gastrointestinal decompression, inhibition of secretion digestive juice and reoperation. Acute retension of urine occurred in 1 case after urine catheter removed. The symptoms disappeared after excises of bladder function. These cases were followed up for 3-36 months (mean 20 months). All the patients recovered to normal function of defecation. Conclusion The technical keypoints of the second-phase diaplasis treatment after Hartmann operation are how to find and liberate the end of the distal colon. It will affect the prognosis and the occurrence of complications after this operation.