Objective. The genetic stability of Strains of Leptospira spp., maintained under two conservation systems, was evaluated. Methodology. The degree of conservation of the 16S rRNA and ompL1 genes of 10 reference serovars from the Leptospira spp. collection, belonging to the Sistema de Bancos de Germoplasma de la Nación para la Alimentación y la Agricultura (SBGNAA), was determined. Results. It was corroborated that the genes evaluated these have not undergone considerable changes, since similarities greater than 99.69 % were evidenced for 16S rRNA and 99.02% for ompL1, in the paired alignments. Conclusion. The genetic stability and purity of the reference strains of Leptospira spp. were verified. spp., kept in cryopreservation in liquid nitrogen at -196 °C and at room temperature for approximately eight years.