Objective To investigate the relevance between angiotensin-converting enzyme（ACE） gene single nucleotide polymorphism（SNP） and chronic obstructive pulmonary disease（COPD） of stable period with lung and kidney qi deficiency syndrome. Methods A total of 95 patients with stable COPD were selected as the case group.According to the traditional Chinese medicine（TCM） syndrome differentiation criteria

they were divided into a lung and kidney qi deficiency syndrome group（37 cases） and a non-lung kidney qi deficiency syndrome group（58 cases）. The other 82 healthy people were selected as the control group. The genomic DNA of all subjects was extracted and the ACE gene SNP（I/D） was detected by PCR

and the polymorphism was verified by sequencing. Results The frequency of distribution of II

ID and DD genotypes in the 95 patients was 44 cases（46. 32%）

38 cases（40%）

and 13 cases（13. 68%）

respectively. The control group was 33 cases（40. 24%）

40 cases（48. 78%）

9 cases（10. 98%）. The lung and kidney qi deficiency syndrome group was 16 cases（43. 24%）

17 cases（45. 95%）

and 4 cases（10. 81%）

respectively. The non-lung kidney qi deficiency group was 28 cases（48. 28%）

21 cases（36. 21%）

and 9 cases（15. 52%） respectively. There was no significant difference in the correlation analysis of the ACE gene SNP（I/D）（rs4646994） among the groups（P > 0. 05）. The results of the SNP sequence query showed that rs4646994 was an I/D mutation of a 289 bp repeat

but the known mutation frequency was less than 1%. Conclusion The ACE gene SNP（I/D）（rs4646994） is not enough evidence for the genetic markers of stable COPD of lung and kidney qi deficiency syndrome. Large samples are still needed for verification.