The present invention discloses polyglycol epoxide crosslinked sodium hyaluronate gel for injection and a preparation method thereof. A polyglycol epoxide is a compound with single molecular weight preferably； a plurality of ether bonds are present in the molecule of the polyglycol epoxide, the water solubility is good, and thus, the polyglycol epoxide is more easily subjected to a crosslinking reaction with polysaccharides； and meanwhile, polyglycol is relatively easy in adjustment of the number of repeating units and relatively easy in control of length, and thus, the sodium hyaluronate gel prepared by taking the polyglycol epoxide as a crosslinker is relatively easy in regulation and control of properties. The crosslinked sodium hyaluronate gel is low in toxicity, little in residual, small in squeezing and pushing force, good in shaping performance, good in enzyme resistance and long in in-vivo retention time. The present invention further discloses a mild crosslinker deactivation technology. Unreacted epoxide groups in the gel are subjected to a hydrolysis reaction in a carbonate buffer system with a pH of 8-9, so that the difficulty of impurity removal of the crosslinked sodium hyaluronate gel can be effectively lowered, and the problem of toxicity in the prior art due to the fact that BDDE is used in a crosslinking method is avoided.
