The invention discloses an organic
boron crosslinking agent prepared by reacting
boric acid with an organic
polyamine compound in the absence of water, wherein the organic
polyamine compound is selected from
diethylenetriamine,
triethylenetetramine, 1,4,7,10,13-pentaazatridecane,
polyethylene-polyamines or polyethyleneimine. The invention also discloses a
guar gum
fracturing fluid, which includes,by weight, the following components:0.2%-0.6% of
hydroxypropyl guar gum, 0.2%-0.6% of the organic
boron crosslinking agent described in claim 1, 0.01%-0.2% of a pH regulating agent, 0-0.5% of a temperature stabilizer, 0.2%-2% of other additives, with the balance being water. The organic
boron crosslinking agent of the invention has a large molecular volume and a plurality of cross-linking pointsformed with a low-concentration
guar gum
aqueous solution, and so, cross-linking properties and
temperature resistance performance of a gelled
fracturing fluid are improved, the using amount of the cross-linking agent is reduced, and the cost of a
fracturing fluid system is reduced. The
guar gum fracturing fluid of the invention has good cross-linking properties and good
temperature resistance performance, the concentration of the
hydroxypropyl guar gum can be adjusted according to the reservoir temperature, and the maximum usage temperature is 150 DEG C.