Abstract: In view of the disposal of wasted drilling fluid in environmentally sensitive areas,a wasted drilling fluid innocuous treatment formula has been developed on the basis of determining the dosage of destablizer SD-131,coagulation accelerator SD-132,and dispersant SD-133.After innocuous treatment,the infiltrate fluid of drilling fluid has low chromaticity and low content of suspended materials.Different materials and elements in the infiltrate fluid are indicated by COD:23-56 mg/L,total Cr:0.86-1.12 mg/L,Cr6+ 0.22-0.40 mg/L,and hydrocarbon:2.67-4.23 mg/L,which meet the requirement of innocuous treatment of wasted drilling fluid.The test of the technology in environmentally sensitive area of Wenmi Oilfield shows the drilling fluid still has certain porosity and is similar to soil 20-30 d of drying after treatment,and can bear bulldozer to restore well site.Field test shows the technology can effectively transform and solidify pollutants in drilling fluid.