The first tumor metastasis-suppressor gene, nm23, may have an important role in the pathogenesis of endometriosis (EM). The present study aimed to evaluate whether nm23 gene polymorphisms are correlated with the risk of the development of EM in North Chinese women, as a preliminary study. The case-control study was conducted with 379 EM patients and 384 unrelated healthy controls. Genotyping of two polymorphisms within the nm23 gene promoter region (rs16949649 T/C and rs2302254 C/T) were performed using polymerase chain reaction-restriction fragment length polymorphism. The data showed that the rs16949649 and rs2302254 polymorphisms within the nm23 gene were not associated with the risk of developing EM. There were no statistical differences in the distribution of nm23 genotypes between patients with EM and the control group (P=0.490 and P=0.440, respectively). For the rs16949649 T/C, compared with the C/T + T/T genotype, the C/C genotype did not increase the risk of EM [odds ratio (OR)=0.81; 95% confidence interval (CI), 0.57-1.17]. For the rs2302254 C/T, compared with the C/T + C/C genotype, the T/T genotype did not increase the risk of EM (OR=1.46; 95% CI, 0.81-2.64). In conclusion, the findings in the present pilot study suggest that nm23 polymorphisms do not contribute to EM susceptibility. However, more studies in larger populations are required to confirm these results.