Five polymorphic microsatellite loci were developed from genomic DNA of red snapper (Lutjanus campechanus) and used to evaluate genetic variation among 194 red snapper sampled from three locations in the northern Gulf of Mexico and one location off the northern Yucatan Peninsula.  From 5 to 13 alleles were observed per locus, and observed heterozygosities ranged from 0.143 to 0.779.  No significant departures from exceptions of Hardy Weinberg equilibrium were found at any locus either within samples or when samples were pooled across localities. Locus-by-locus test of allele-frequency homogeneity over the four localities were non-significant. Weir and Cockerham’s at each locus ranged from -0.003 to 0.0012, and Statkin’s RST at each locus ranged from -0.014 to 0.008. None of the estimates of and RST differed significantly from zero, and magnitudes of and RST did not appear to vary with geographic distance between localities. These results are consistent with the hypothesis that red snapper at these localities comprise a single population. There are, however, a number of caveats to this hypothesis. Detection of population structure of red snapper in the Gulf may require larger numbers of samples, and the importance of importance of local reproduction to recruitment needs to be examined via examination of larvae settling onto reefs. There was a positive but non-significant correlation between mean number of repeat units per microsatellite allele and heterozygosity of the locus.