The existing self-heating system usually begins to generate heat during the ground preparation process，and then the heat and gas generated lost during transportation，making it difficult to efficiently act on the target layer. At the same time，for low-permeability reservoirs，the high surface tension of fracturing fluid leads to a low wave coupling coefficient in the target reservoir， which affects the multi-scale fracturing and crude oil driving capabilities of the fracturing fluid. Aiming at the performance defects of the thermal fracturing fluid mentioned above，a novel sustained self-heating energy-enhancing oil displacement fracturing fluid system was developed. Based on the exothermic reaction of carbamide and sodium nitrite in hydrochloric acid solution，the self-heating system was prepared by adding hydrochloric acid solution with free or water in oil emulsion liquid respectively. A small molecule polymer enhanced oil displacement agent was prepared using maleic anhydride，2-acrylamido-2-methylpropanesulfonic acid，dimethyl succinate， glycidyl methacrylate，acrylamide，and sodium ethylbenzenesulfonate as monomers. This article studied the sustained heat generation and gas production capacity of the heat generating system，the surface/interface activity and the viscosity reduction ability of the enhanced oil displacement agent，and the compatibility and oil displacement effect of the two. The results showed that the heat generating system could release heat and produce gas twice during the injection process and after 40 minutes of injection，with a temperature of over 80 ℃. It could simultaneously achieve the effects of hot fluid injection and reservoir heating，leading crude oil viscosity reduction and reservoir energy enhancement. When the dosage of enhanced oil displacement agent was 1500 mg/L，the surface tension of fracturing fluid could be reduced to 25 mN/m，the interfacial tension between fracturing fluid and crude oil could be reduced to 0.0008 mN/m，and then the viscosity of crude oil at room temperature could be reduced from 152.8 mPa·s to 38.2 mPa·s. The compatibility between heat generating system and oil displacement agent was good. The mixture remained stable even after 12 hours of static mixing. The recovery rate of compound use was significantly higher than that of water flooding by 19.5 percent points.