Abstract: This paper reviewed the introduced genetic resources of Populus in different phases briefly, and summarized the important role of introduced resources in cultivating and the breeding. The authors considered that the research should be strengthened according to the problems presented nowadays. It is necessary to increase the investment to the research of genetic resources, build up the perfect base of genetic conservation, strengthen the innovative abilities to the poplar breeding, extend the scale and the profundity of the estimate research of the introduced genetic resources to achieve the abilities of foreseeing the use of the introduced genetic resources. The gene saturation to poplar hybrids can change the genetic diversity and the integrality of native poplar, the artificial hybrids transformed the foreign genes is the key technology to defend the gene pollution which should be taken as the new needed index to popularize the new varieties. It should start the new turn of collection and research to genetic resources of poplar in order to do the foreseen prepare of the new needed varieties for the intensive management benefit (cultivated range moved to north and the grown period prolonged) which is brought by climate change, the potential ecology risk (absent water) and the disaster brought by insect or disease.