Objective To evaluate whether to defer abdomen surgery in patients having poorly controlled or untreated hypertension before operation. MethodsThe perioperative clinical data of 531 patients with hypertension in our hospital from January 1997 to December 1998 was retrospectively analyzed. ResultsThe modility of perioperative hypertensive events was not significantly different, between controlled and uncontrolled patients with grade one and grade two（Pgt;0.05）. In grade three and systolic hypertension, certain complications in patients with poorly controlled hypertension were higher than in those with wellcontrolled hypertension（P＜0.05）. Conclusion The patients with grade one and grade two hypertension are not at increased operative risk. In patients with grade three and systolic hypertension, perioperative complications are increased and elective surgery should be postponed until their blood pressure is brought under 24/14.7 kPa （180/110 mm Hg） over 1 to 2 weeks.