Abstract: Objective To investigate the effect of Betatrophin on glucose metabolism in polycystic ovary syndrome patients. Methods From January, 2016 to June, 2017, we prospectively collected 50 cases of polycystic ovary syndrome patients in our hospital as an observation group, while 50 healthy adults were collected as a control group. The Betatrophin, Matsuda index, HOMA-IR, HOMA-β, blood glucose and insulin levels of the both groups were compared. Moreover, the association between Betatrophin and glucose metabolism indexes was studied. Results When compared with the control group, patients in the observation group got a reduced Betatrophin[(0.82±0.08) ng/ml vs. 0.91±0.08 ng/ml,P<0.001]; a decrease in Matsuda index (4.82±1.10 vs. 5.37±1.38, P=0.030); an elevated HOMR-IR (2.84±0.64 vs. 2.51±0.75, P=0.020); an elevated HOMA-β (195.39±45.12 vs. 175.38±40.58, P=0.022); a higher level of glucose 30 min OGTT[(145.92±21.58) mg/dl vs. (128.38±23.58) mg/dl, P<0.001]; an increase in glucose 60 min OGTT[(123.72±29.81) mg/dl vs. (97.58±12.48) mg/dl, P<0.001]; an elevated insulin 30 min OGTT (89.75±30.12) vs. (63.58±23.58) μIU/ml, P<0.001); a higher level of insulin 60 min OGTT (80.81±25.12 vs. 61.58±20.71 μIU/ml, P<0.001); and an increased insulin 120'B OGTT (55.31±15.87 vs. 35.93±12.65 μIU/ml, P<0.001). The Betatrophin was positively correlated with the HOMA-IR and HOMA-β (P<0.05), and negatively correlated with Matsuda index, blood glucose 30'B OGTT, insulin 30'B OGTT, insulin 60'B OGTT and insulin 120'B OGTT (P<0.05). Conclusion Impaired glucose tolerance in polycystic ovary syndrome is related to the reduction of Betatrophin.