The new oil-based completing fluids technologies to protec the reservoir were reviewed,especially the low-solid high -density W/O emulsion mud was emphasized,which was successfully applied in North Sea of Norway as perforation fluid.

In the application of ultra low-density drilling fluid,compared with conventional oil base drilling fluid,the invert emulsion mud is easy to ignite and has poor safety while hollow micro-sphere glass beads polysulfonate drilling fluid by American 3M Company has not only technical difficulties in controlling the volume of solid phase but also high cost in drilling fluid.

Wettability reversal agent is an important additive for oil base drilling fluid.

Technology study of pseudo oil-based drilling fluid;

Study on synthesis of fluid loss reducer for oil-based drilling fluid by modifing humic acid;

At present, waste oil-based drilling fluid is often treated by the ways of central landfill and re-injection into formation, which does not solve the problems of pollution to environment and much diesel wasting.

Mud logging technique improvement and practice with oil-base drilling fluid;

Meanwhile,the paper proposes that using oil-base drilling fluid can prevent the reservoir damage.