Fifteen microsatellite loci (D3S1358, TH01, D21S11, D18S51, PENTA E, D5S818, D13S317, D7S820, D16S539, CSF1PO, PENTA D, vWA, D8S1179, TPOX, and FGA) have been genotyped in four indigenous populations from El Salvador (Central America), namely, Conchagua, Izalco, Panchimalco, and San Alejo. Here we have obtained values for several indices of forensic interest for these population samples. Population differentiation test showed no significant statistical differences between these four populations, and an AMOVA test indicates that most of the genetic variation (approximately 100%) occurs within individuals. Population pairwise genetic comparisons with other population samples seem to indicate the existence of a major Native American component in the populations from El Salvador.