：Through investigating the proppant-carring time (Time) of the fracturing fluid,the optimal content of borax, complexing agent, solvent to prepare the organic boron crosslinker YJ-P had been ditermined.In addition,viscoelastic property of the fracturing system had studied by the dynamic rheology . The results showed that, when borax content was 25%, compound complexing agent ratio (m (glucose) : m (MEG)) was1:1.5, ratio of glycerol to water was 6:1 and content of crosslinking agent was 1.2% with low concentration of guanidine gum fracturing fluids, the fracturing system had the optimal proppant-carring performance, the proppant-carring time reached 27 min•mm-1.When the reaction time was determined as 4.0 h, reaction temperature as 80 ℃, the optimal proppant-carring capability of modified organic boron crosslinking agent on the low concentration guanidine gum fracturing fluid had shown up. When minimum effective concentration of guanidine gum reached 0.2%, the dynamic modulus increased with the growth of angular frequency.When the angular frequency was up to 10 rad.s- 1, the G '> G "and G' > 0.1 Pa. The fracturing fluid had optimal viscoelasticity.