Abstract: The big angles characteristic of highly deviated well objectively determines great difficulty in casing cementing process and the cementing quality is difficult to be guaranteed.Aiming at this problem of Chenghai block-2 in Dagang oilfield,the influencing factors analysis of the cementing quality has been carried out.The results show that by optimizing the cementing process,optimizing slurry system with characteristics of short thickening transition time,strong channeling prevention performance and small drainage,water oil and gas channeling can be effectively prevented.Through optimizing the borehole conditions,optimizing displacement fluid displacement,optimization of drilling fluid performance and optimization of casing in the moderate,displacement efficiency can be improved and the quality of well cementation can be effectively guaranteed.