Objective To investigate the relationship between HLA-DRB1 alleles and vascular anomalies in infants of Han nationality in Guangxi Zhuang Autonomous Region.Methods This study included 145 infants with vascular anomalies (99 cases of hemangioma (hemangioma group) and 46 cases of vascular malformation (vascular malformation group)) and 105 healthy infants (control group) of Han nationality residing in Guangxi Zhuang Autonomous Region.The genotypes of HLA-DRB1 alleles were determined by using PCR-sequence specific primers (PCR-SSP).Chi-square test was performed to analyze the difference in the frequency of HLA-DRB1 alleles between these groups by using the SPSS 16.0 software.Results There were significant differences in the frequency of HLA-DRB1*0901,*1401 and *16 alleles among the hemangioma group,vascular malformation group and control group (x2 =13.05,12.79,10.36,respectively,all P ＜ 0.01).Paired comparison revealed significant differences in the frequency of HLA-DRB1*0901 allele between the hemangioma group and vascular malformation group (RR =4.84,P ＜ 0.01) as well as between the hemangioma group and control group (RR =3.21,P ＜ 0.01),and in the frequency of HLA-DRB1*16 allele between the hemangioma group and control group (RR =2.25,P ＜ 0.01) as well as between the vascular malformation group and control group (RR =2.60,P ＜ 0.01).The frequency of HLA-DR*1401 allele was significantly lower in the hemangioma group than in the control group (RR =0.30,P ＜ 0.01).Conclusions HLA-DRB1*0901 and *16 may be the predisposing genes for hemangioma and vascular anomalies respectively,while HLA-DRB1*1401 appears to be protective against hemangioma,in infants of Han nationality in Guangxi Zhuang Autonomous Region.