Abstract: Super-fine cement plugging technique takes super-fine cement as the main agent,which is compounded with several additives to form a plugging agent of grain type with high strength.Based on research on formula-tion,properties and applicability of the plugging agent,plugging operation can be performed in case of external casing channeling,casing screw leaking,leakage through corrosion puncture of casing and abandoned injection lay-er.Field application in Henan oilfield show that plugging effects are good and success rate is high.