Ｏｂｊｅｃｔｉｖｅ　To investigate the association between postoperative sufentanil consumption and genetic polymorphisms of mu-opioid receptor (OPRM1), ATP-banding cassette, subfamily B, member 1 gene(ABCB1) and CYP3A in postoperative tumor patients.　Methods　A total of one hundred and twenty patients [American Society of Anesthesiologists (ASA) Ⅰor Ⅱ, aging 19 to 65] who were scheduled to undergo tumor surgery under general anesthesia were enrolled in this study. Intravenous patient-controlled analgesia with sufentanil was provided postoperatively. Cumulative sufentanil consumption was measured 2, 6, 12, 24 h and 48 h after surgery. The severity of pain was assessed with the Visual Analogue Scale(VAS), while OPRM1 118A>G, ABCB1 2677G>A/T, ABCB1 3435C>T, and CYP3A4*1G and CYP3A5*3 variant alleles were detected. The effects of genetic and non-genetic factors on sufentanil requirements were evaluated with multiple linear regression analysis.　Results　Patient VAS scores 2, 6, 12, 24 h and 48 h after surgery were obviously associated with cumulative sufentanil doses (P<0.05). The 48 h cumulative sufentanil dose after surgery was associated with age(P<0.05).　Conclusions　There was no association between OPRM1, ABCB1, CYP3A genetic polymorphisms and postoperative sufentanil consumption in tumor patients.