Abstract: Cementing of the slim hole is very difficult due to its small hole size and annular clearance, and the conventional cementing technology cannot meet the requirements of field cementing. The slim wells drilled in Changqing are relatively shallow, and formations are low pressured with low permeability. Water layers or bottom water also exist in the pay zone. In accordance with these conditions, and based on the cluster well development plan, a practical slim hole cementing technology is developed and field applied, with remarkable improvement on cementing quality. Its technique, study achievements on cement slurry, and field using are described.