In order to prepare slickwater with produced water directly and simultaneously reduce its adsorption damage to reservoir， a drag-reduction agent called NY with high salt tolerance and low adsorption was synthesized by introducing polar cation fragments. Corresponding slickwater system was compounded with NY and other additives，including clean-up additive and clay stabilizer. The formula of slickwater system was optimized by evaluating its comprehensive performance. Finally，the slickwater system was applied in the shale block of Sichuan basin. The experiment results showed that NY had high salinity tolerance and drag reduction， with drag reducing rate over 70% in high salinity condition（≤300 g/L），and exhibited good compatibility with other additives. The corresponding slickwater system also showed high salinity tolerance and drag reduction. When the salinity was 0—300 g/L，the sticky time of slickwater system was shorter than 60 s，together with apparent viscosity of 1—3 mPa·s. Meanwhile，the surface tension was less than 30 mN/m，the anti-swelling rate exceeded 80% and the shale adsorption capacity was less than or equal to 3.66 mg/g，which completely satisfied the requirements of industry standard and field operation. The application of slickwater system showed that both of the success rate of fracturing operation and reuse rate of produced water were 100% in 8 wells. Compared with conventional slickwater system，this novel slickwater system had low adsorption and reservoir damage. Meanwhile，the overall liquid cost reduced by 17% and the production rate per well increased by 44%，indicating remarkable results were achieved in field application.