Abstract: The Hezuo swine SLA-DQA gene adaptive mutation, antigen recognition region（exon 4）by PCR amplification and subsequent single-strand conformation polymorphism（SSCP）and sequence analysis . The results show that 439 Hezuo swine individual SLA -DQA exon 4 detection of three alleles and six genotypes（AA, BB, CC, AB, AC, BC）the highest frequency of the A allele and AA genotype, genotype was the dominant gene and advantages .On a different type of PCR-SSCP pieces with sequencing analysis found that the fourmutated sites（5 068 bp T→C, 5 109 bp and 5 149 bp insert C, 5 131 bp A → G cause serine into glycine, 5 135 bp C → T, at 5 136 bp insert A, the 5 234 bp G → A lead tyrosyl acid becomes cysteine.Genetic analysis：cooperation pig polymorphic information content（PIC）was 0.240 1, belongs to the moderate polymorphism；significant distribution of various genotypes .The findings confirm that cooperation pig SLA - DQA gene the 4 exon has low rich genetic polymorphism .