Medicago species are important genetic sources for forage crops and nitrogen sources for various ecosystems. The ongoing genome sequencing of the model legume, Medicago truncatula, provides a wealth of genetic markers potentially useful for characterizing the population genetic structure and evolutionary history, and the potential of the wild Medicago species. Here we tested the PCR amplification of 92 microsatellites developed from M. truncatula in six other Medicago species, and found that the cross-species transferability, ranging from 53.26% to 61.96%, is comparable with those reported in other angiosperm genera. This article thus reports a number of microsatellites that are potentially useful for large-scale ecological and evolutionary genetic studies of wild Medicago species.