Restricted gene flow may cause positive genetic spatial autocorrelation of animal populations at fine spatial scales.The Mongolian Gerbil is a territorial,social rodent.Territoriality may create social fences to restrict the dispersal or gene flow of Mongolian gerbils to short distance.Competition for mates and inbreeding avoidance may result in equal dispersal propensity and similar genetic spatial autocorrelation between the males and females of monogamous Mongolian gerbils.We genotyped 327 individuals captured from 26 burrow systems on a 9-ha plot with seven microsatellite loci to study the fine-scale spatial population genetic structure of Mongolian gerbils.Fine scale genetic spatial autocorrelation was positive in a distance of less than 80 m and became negative in a distance from 80m to 200m in the male juvenile subpopulation,the female juvenile subpopulation,and the entire population.Inter-individual genetic and geographic distances were positively related,supporting the isolation by distance model.Additionally,live trapping data demonstrated the breeding dispersal of females and equal dispersal propensities between males and females,with average dispersal distance from 60 m to 80m.Therefore,restricted gene flow or short-distance dispersal may maintain high genetic relatedness among individuals within a distance of about 80 m,resulting in positive genetic spatial autocorrelation in both sexes.Social organization and restricted dispersal may result in complex fine-scale spatial population genetic structure of small mammals.