The invention discloses a biomedical 
adhesive for crosslinking reaction with 
wound skin tissues and a preparation method thereof. The biomedical 
adhesive is prepared by a method with following steps of firstly, using 
sodium periodate and oxidized 
sodium alginate to prepare dialdehyde 
sodium alginate, dialyzing, 
drying, and dissolving a product into an MES (methyl 
ester sulfonate) 
buffer solution; then, adding 
carboxymethyl chitosan, stirring and reacting for 6-12h, sequentially adding a certain amount of N-hydroxy 
succinimide, 1-(3-dimethylamino propyl)-3-ethylcarbodiimide 
hydrochloride and 
dopamine, continuing to stir and react for 8-24h under the 
nitrogen protection, dialyzing, freeze-
drying, and storing in the shade and dry area. Before use, a wound is pretreated by 
hydrogen peroxide, the freeze-
drying adhesive is dissolved by a PBS (poly butylenes succinate) 
buffer solution, and is immediately coated to the wound, and the wound can be adhered within 2-10min. The biomedical adhesive has the advantages that the adhering strength in the in-vitro 
wetting environment is stronger, the 
biocompatibility is good, the 
biodegradation is realized, and the curing of wounds is effectively promoted.