The treatment technologies of waste drilling fluid in drilling engineering both in China and abroad were introduced. The hazard and influence to environment by waste drilling fluid was studied. The treatment technologies and methods such as the in-pit landfill, solid-liquid separation, solidification and recycling use were discussed. Some suggestions were put forward, such as developing new environmental protection drilling fluid and additive, strengthening the solid control, reducing the discharge of waste drilling fluid and comprehensively developing new technology like microbial method. All the above can be the reference to environmental protection in other similar areas.