Abstract: The populations of Populus alba present a independently distributing pattern of male or female patch. To realize the form reason and distributing mode, we selected 12 microsatellite primers to study the clonal structure and clonal diversity of Populus alba base on two sampling strategy. The result showed that: (1) all swatches in a single distributing patch of male or female were a identical clone, the single patch had only one genet; (2) we differentiated 53 genotypes(genet) among the 90 plants sampled of all patches. The populations of Populus alba had an abundant clonal diversity and the mean Simpson’s index was 0.983, and mean PD was 0.589. The progeny of Populus alba was reproduced by root clone. The high clonal diversity might be maintained if the populations were initially founded by multiple genets that differed genetically and the existent frond was the progeny of clonal genets.