Objective To explore clinical characteristics of patients with Klinefelter′s syndrome(KS; 47,XXY).Methods 227 male patients with 47,XXY treated by artificial insemination with donor(AID)were included.Age, education, height, weight, body mass index(BMI), testicular volume, FSH, LH, testosterone(T), prolactin(PRL), estradiol(E2)were analyzed retrospectively.Results Of these patients, their height were(176.4±5.5)cm, weight(74.5±12.7)kg, BMI(23.89±3.66)kg/m2[77 of overweight(33.92%)and 34 of obesity(14.98%)], FSH(38.35±14.33)IU/L, LH(19.40±9.00)IU/L, T(132.00±194.50)ng/dl, E2(23.90±15.00)ng/L, PRL(10.50±8.20)μg/L, E2/T 0.21±0.80.Testicular volume had the positive association with the level of T(r=0.197, P=0.003).BMI had the negative association with the serum concentration of T(r=-0.284, P=0.000), while positive association with the E2(r=0.174, P=0.009)and ratio of E2/T(r=0.323, P=0.000).Age had no association with T, E2, and E2/T(P>0.05), but had negative association with the serum concentration of LH(r=-0.154, P=0.02)nd FSH(r=-0.196,P=0.03).The higher education group were older(P<0.01), while the level of T were lower(P<0.01).Conclusion In patients with Klinefelter′s syndrome(KS; 47,XXY), level of T may associate with testicular volume.T, E2, and the ratio of E2/T seem to associate with their height, BMI, and education level.