In order to find out the causes, diagnosis, and the prevention and treatment of vascular crisis following anastomosis of small vessels, 314 cases vascular crisis from 1985 to 1997, were analyzed, in which 152 cases, suffered from tissue necrosis either total or partial, making up 48.4%. One hundred and forty-four cases underwent conservative treatment occupying 45.8% and 104 cases had tissue necrosis, occupying 68.4%. Operative exploration was done on 170 cases, occupying 54.1% and 48 cases of them suffered from necrosis, which made up 31.6% of all necrotic cases. Eighty-six cases were followed up by regular visits, ranging from 40 days to 7 years, with the finding that those who had regained normal circulation after vascular crisis recovered as well as those without crisis, and among those who did not regain normal circulation but survived with the help of collateral circulation after vascular crisis, they were usually cases of bad union, healing of wound, persistent swelling, different degree of tissue atrophy, poor recovery of sensation. It was concluded that proper use of vascular anastomosis technique and prophylactic measures preventing postoperative vascular spasm were extremely important, in the prevention of development of vascular crisis following anastomosis of small vessels. If vascular crisis did not respond well to conservative treatment, prompt surgical exploration should be undertaken.