Background: Tuberculosis (TB) is a highly prevalent chronic infectious disease in developing countries, with Peru being one of the most affected in the world. The variants in Nacetyltransferase 2 (NAT2) gene are related with xenobiotics metabolism and have potential for TB studies. Aim: Associate the NAT2 gene variants, acetylator phenotypes and active tuberculosis in Peruvians patients. Methods: The design was cases (TB patients) and controls (population-based data). First, DNA isolation, and the variants rs1799929, rs1799930, and rs1799931 of the NAT2 gene were determined with sequencing. The acetylator phenotypes: Slow (SA), intermediate (IA) and rapid (RA) too were analyzed. Results: The frequencies of the rs1799931 variant in the patients, respect controls, showed significant differences and they are risk, both for the A allele (p=0.00; OR = 3.04, 95% CI: 1.88- 4.9) and the AG genot...