Abstract: Populus pruinosa only naturally distributes in the Tarim basin of Xinjiang, Northwest China. In this paper, field investigation and laboratory analysis were conducted on the adults, samplings, and 1-year old seedlings of P. pruinosa, aimed to understand the spatial distribution of the clonal reproduction organs of P. pruinosa and the relationships of this distribution with clonal reproduction. The clonal reproduction organs of P. pruinosa were all the first order horizontal lateral roots on the taproots. The clonal reproduction organs and taproots formed in nearly 90 degree angle, and carried on vegetative growth and horizontal expansion in soil until they grew to a certain stage and penetrated vertically at particular space sites. The same taproots had different first order horizontal lateral roots, whose horizontal expansion parts were in the 10-100 cm soil layer and concentrated in the 20-40 cm layer. Different horizontal lateral roots had different distribution depth, extending direction, and expansion distance in soil, and even, different sections of the same horizontal lateral roots also had different distribution depth, extending direction, and expansion distance in soil. In different habitats, P. pruinosa could generate the horizontal lateral roots with almost unanimous vertical distribution. The generated horizontal lateral roots could produce clonal ramet, and were mainly distributed in the 5-30 cm soil layer. Underground water level could affect the occurrence of the clonal reproduction of horizontal lateral roots.