Abstract: Establishing core collection of Eucalyptus urophylla can identify quickly and accurately the superior gene sources from its rich and diversified germplasm resources that is urgently requested by breeding practice. The primary core collection of E. urophylla was selected by different sampling proportion according to 5 parameter values, i.e., the mean value, variance, range, coefficient of variation and average diversity index values of the E. urophylla phenotypic properties of the genealogies. The primary core collection was grouped by the geographical provenances, then compared and analyzed by different sampling proportion according to the 4 parameters including MD, VR, CR, VD to build the secondary core collection of E. urophylla by means of LDSS method. As the result, totally 188 pieces of secondary core collection were screened out which accounted for 10% of the whole resources. It was tested that the genetic characteristics controlling different character phenotypic correlation were also well remained in the secondary core collection. The constructed secondary core collection resources of E. urophylla might be treated as the representative samples, which would play a very important role in utilizing the E. urophylla resources.