Abstract: Fracturing fluids containing 0.45%-0.50% guar gum had always been used in the stimulation of high temperature, low porosity, low permeability reservoirs. High concentration of guar gum resulted in serious damages to reservoirs and high operation cost. Laboratory studies had been conducted to try to minimize the use of guar gum and to enhance the thermal stability of fracturing fluids. A high performance guar gum and a cleanup additive of low surface tension were selected for use with the newly developed multi-group crosslinker with bigger hydrolysis radius. Using these additives, a fracturing fluid with high thermal stability and low guar gum concentration was developed. This fracturing fluid had guar gum concentrations of 0.30%-0.35%, with its properties remained stable between 120-130℃. This fracturing had the advantages of complete gel breaking(η<8 mPa·s), low residue(117 mg/L), slight damage to reservoir permeability(<10%), and good rheology. It was successfully used in fracturing operation in the Well Tahe535.