Abstract: Objective: To observe the effect of anesthetic remifentanil combined with isoflorane in controlled hypotension in meningiomas surgery and its influence on the surgical field quality and stress reaction.Methods: Forty patients with ASA gradeⅠ-Ⅱ undergoing selective endoscopic sinue surgery were randomly divided into remifentanil group(R group) and sodium nitroprusside group(F group).The blood pressure,heart rate and the surgical field quality were compared between the two groups before anesthesia and during controlled hypotension.The surgical field quality was also determined during controlled hypotension.Results: The systolic blood pressure(SBP) and mean arterial pressure(MAP) of the two groups during controlled hypotension were lower than before anesthesia(P<0.01).The SBP,MAP and HR were lower in group R than in group F during controlled hypotension(P<0.01).Compared with group F,the surgical field quality in group R was significantly better.The trend curves showed that the heart rate was stable in group R compared with that in group F(P<0.01).Conclusions: Remifentanil is effective in controlling the blood presure during meningiomas surgery,which may provide a better surgical field quality and inhibit the stress response.