Abstract: As oil and gas exploration and development proceeds,the objective become more and more complex,the requirement on cementing quality becomes higher and higher,and well cementing is facing more and more challenges.Based in the analysis of the cementing situation confronted by CNPC,major advances in cementing technology in recent years are summarized including cementing process,additives and cement slurry system,cementing tools/equipment and fundamental research.Challenges are analyzed from six different aspects,including cementing in complex deep ultra-deep wells and complicated formations,cementing in complex natural gas wells and acid gas reservoirs,cementing in shale gas and tight oil/gas wells,cementing in underground gas storage,cementing in overseas complex blocks,and cementing in offshore low temperature deep-water wells.Key technologies to ensure long-term effective zonal integrity of oil and gas wells are summarized.It is suggested that more efforts be put into fundamental research,cement slurry system development,and cementing technology and cementing tools/equipment development,which are some of the tricky points in future technology research.