Surfactant fracturing fluid system and preparation method thereof

The invention discloses a surfactant fracturing fluid system, which comprises the following components, by mass percentage: 0.3-0.5% of long-chain alkyl amidopropyldimethyl amine oxide, 0.15-0.4% of long-chain alkyl amido betaine, and 0.1-0.2% of an additive, with the balance being water. The invention further discloses a preparation method of the surfactant fracturing fluid system. The method comprises: dissolving the additive in water at the room temperature under the normal pressure, adding long-chain alkyl amido betaine and long-chain alkyl amidopropyldimethyl amine oxide in sequence, and performing uniform stirring to obtain the surfactant fracturing fluid system. The surfactant fracturing fluid system has slight damage to the ground and is low in pollution and good in flowback ability, no chemical agent is needed for gel breaking, and the residue content of a fracturing fluid is almost none. The system can effectively stabilize clay, causes slight surface effect and pollution to the oil source bed during a fracturing process, even no pollution, can effectively increase the production capacity of an oil well, and achieves the purpose of hydrocarbon reservoir fracturing. The method is simple to operate, is eco-friendly, and is suitable for industrial mass production.