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In order to estimate the potential of biological nitrogen fixation by Cajanus cajan L., Canavalia ensiformis L., and Mucuna deerengiana L., in rotation and association with maize, two experiments were carried out during two crop cycles in the acidic soil of the Huimanguillo savanna, Mexico. In both systems, the nodulation of fabaceae and its effect on maize (Zea mays L.) grain yield were evaluated. The derived N from the atmosphere (FBN) and the N absorption efficiency by the maize crop were quantified through the 15N isotope technique. The results show that C. cajan L., produced 66 to 121, C. ensiformis L., 38-80 and M. deerengiana L., 45-78 nodules plant-1, with maximum MS from nodules 14, 7 and 4 g plant-1 in association and in rotation, respectively. Biomass production by these fabaceae was 5.780 for C. cajan L., 7.037 for C. ensiformis L., and 5.284 kg ha-1 for M. deerengiana L. when in association with maize. The grain yield of the different genotypes of maize in rotation and in association ranged from 580-642 kg ha-1. The N fixed by these fabaceae in rotation is considered very low (2 kg N ha-1), while a higher FBN occurred in the association fabaceae-maize (135 kg N ha-1). However, high FBN did not produced more grain yield when compared to the witness groups. [ABSTRACT FROM AUTHOR]