To associate some polygenic phenotypes with discrete regions of the genome (QTL's) it is necessary to have at one's disposal some known and positioned molecular markers to detect linkage disequilibrium that allow us to detect those associations. The microsatellites, due to their abundance, due to the high level of know ledgement of their position in the pig genome and due to the high polymorphism, are suitable to do this approach. This work has been done to select the appropriate microsatellites for a pluridisciplinar project to detect QTL's associated to meat quality in the Iberian pig and the Landrace pig. To manage that we bear in mind their position in the genome and their interpopulation variability, that means, their informativity. This has been calculated by means of an stadistic based on the frequences, in one population, of the alleles in the other population.