R&D of high effective purifying chemicals is one of the bases and keys in treating effluent from in-situ heavy oil recovery according to its characteristics such as high viscosity, low oil/water ratio, serious emulsification, high temperatureand wide variation.Experimental results demonstrate that oil content, SS and COD in the treated water are about 1mg/L, 4 mg/L and 200 mg/L respectively, and their removal efficiency can reach over 99.9 %, 98.5 % and 96.9 %respectively when dosages of chemicals TJ -1 and flocculating agent P -3 are at the rang of 75 ～ 100 mg/L and 1 ～ 3mg/L respectively,at the same time, GT values are controlled at the rang of 10⁴ ～ 10⁵.