In order to improve the heat resistance and lower the cost of clean fracturing fluid，a Gemini cationic surfactant GX22 was synthesized by long carbon chain alkyl amide propyl dimethylamine，epoxy chloropropane and hydrochloric acid. The heat resistance and rheology of clean fracturing fluid consisting of GX22 were investigated. The results showed that GX22 could form micelle system in aqueous solution without salt. The clean fracturing system was characterized by significant shear thinning property，and the flow curve of system could be described by Cross constitutive equation model. The thixotropy enhanced withincreasing GX22 concentration，which meant the structural strength was stronger. The elastic modulus G' and viscous modulus G'' both increased when angular frequency increased，and G' was always greater than G''，which indicated that the elastic modulus of fluids was predominant. The viscosity of clean fracturing fluid with 3% GX22 was 33.53 mPa·s after shearing for 90 minutes at 110℃ and 170 s^-1，showing good temperature resistance. Compared with the same type of clean fracturing fluid，the clean fracturing fluid with GX22 had such features as simple synthetic process，available raw materials and without product reprocess of GX22，easy preparation and low cost of fracturing fluid.