Abstract: Objective To determine the distribution of N-acetyltransferase 2 (NAT2) genetic polymorphisms in Chinese Hans TB patients.  Methods The specific gene sequence of NAT2 from peripheral blood lymphocytes were detected by PCR-DNA sequencing technique and the common sites of single nucleotide polymorphism were analysed. These Results were compared with the data of healthy population reported in other articles.Results Of 155 Chinese Hans TB patients, the alleles genetic frequencies of NAT2*4, NAT2*5A, NAT2*5B, NAT2*5C, NAT2*6, and NAT2*7 were 50.7%, 0.6%, 4.8%, 1.0%, 28.7% and 14.2% respectively. 11 genotypes as follow were detected: NAT2*4/4, NAT2*4/5A, NAT2*4/5B, NAT2*4/5C, NAT2*4/6, NAT2*4/7, NAT2*5B/6, NAT2*5B/7, NAT2*6/6, NAT2*6/7 and NAT2*7/7. According to the metabolic phenotype, these genotypes were divided into fast type（NAT2*4/4）, intermediate type（NAT2*4/5A, NAT2*4/5B, NAT2*4/5C, NAT2*4/6, NAT2*4/7） and slow type (NAT2*5B/6, NAT2*5B/7, NAT2*6/6, NAT2*6/7, NAT2*7/7). And their frequencies were 23.2%，54.9%（1.3%，3.2%，1.9%，34.9%，13.6%），and 21.9% (1.9%，4.5%，5.8%，9.0%，0.6%), respectively.There are significant difference in the phenotype distribution between TB patients and healthy population (χ²=11.93，P<0.01). Conclusion s The intermediate type of NAT2 genotype in Chinese Hans TB patients was main form, and NAT2 genotype distribution may be associated with TB susceptibility.

Key words: tuberculosis/enzymology, arylamire N-acetyltransferase, polymorphism,genetic, Han nationality