The poor sand-carrying performance，insufficient energy enhancement capability and low imbibition displacement efficiency of conventional slickwater fracturing fluid caused by the great difficulty in entering the micro-nano scale pore throat， have been a problem in fracturing stimulation in shale reservoirs. To solve this problem，a supramolecular fracturing fluid system suitable for volumetric fracturing of shale oil was constructed based on the hydrophobic association effect between quaternary ammonium amphoteric polyacrylamide copolymer drag reducer （RW） and anionic-nonionic compound surfactant （mixture of alkylphenol polyoxyethylene ether and α-olefin sulfonate）nanoemulsion（DO-2）. The formula of slick water was 0.1% DO-2 and 0.1% RW，and then that of sand carrying fluid was 0.1% DO-2 and 0.3% RW. The properties of nanoemulsion and supramolecular fracturing fluid were evaluated by measuring the parameters such as static adsorption capacity，contact angle，drag reduction rate， residue amount and core permeability. The results showed that the adsorption loss（about 1 mg/g）on the core surface was low，and the wettability reversal ability was good. The contact angle of oil-wet core surface could be increased from 126° to 154° . The nanoemulsion could smoothly enter and pass through the small pores of reservoirs due to its nano-scale（about 10 nm），resulting in a good potential of imbibition and oil displacement effect. In addition，the viscosity was adjusted by the concentration variation of RW，which could significantly simplify the operation process by the successful realization of on-line preparation. The system had the characteristics of low friction resistance（drag reduction efficiency＞70%），low residue content（25 mg/L of sand carrying liquid），strong wettability alteration（more than 30° the contact angle increase of oil droplets），and low permeability reservoir damage（15.2% the damage rate of sand carrying breaking fluid）. The supramolecular fracturing fluid was applied in 208 horizontal wells of shale oil in Qingcheng oilfield from 2021 to 2023. The initial production of single well increased from 12.6 t/d to 14.0 t/d， while the flowback rate of initial production decreased from 10.5% to 7.1%，which demonstrated a remarkable effect of both increase of production and efficiency. This technology could provide a demonstration and reference for the efficient development of other similar unconventional shale reservoirs.