Xingouzui formation was typical low pressure, low porosity, low permeability and shallow buried reservoir in Wancheng oilfield. To re-treatment successfully and improve postfracture response in the formation, it was critical to select the fracturing fluid system for refracturing, which could be provided with proppant carrying capacity enough, broken and flowbacked easily and low reservoir damage. According to the research in laboratory, a special kind of low damage refracturing fluid system including 0.50% gelling agent HPG, 0.50% cleanup additive BA1-5, 0.50% clay inhibitor BA1-13, 0.20% bactericidal agent BA2-3 and 0.45% crosslinker BA1-21A and BA1-21B (10%—30% NaOH solution) in mass ratio 10:1 was developed successfully. Fracturing fluid evaluating experiment results showed that this system was characterized by excellent anti-shearing performance, as the viscosity of fracturing fluid gel still kept about 120 mPa·s after shearing 2 hrs at 70℃ and 170 s-1, good gel breaking property, as the viscosity of broken-gel fluid was 3 mPa·s with (NH₄)₂S₂O₈ dosage of 500 mg/L, and little damage to the formation, as the formation fracture conductivity was about 116.68 D·cm with the fracture conductivity damage rate about 28% after system breaking. The fracturing fluid system was used to retreatment in W5X well successfully, with 29.3% proppant concentration in average and 4.5~5.0 m³/min construction displacement. The postfracture response was desired whose stable daily fluid production rate was 6.5 t and daily oil production was 5.1 t.