The geographical distribution of the species diversity of the genus Populus in China was studied using the geographical information system and spatial statistics. The relationship between the Populus species diversity and longitudinal and latitudinal bands was analyzed using linear regression analysis. The results showed that:(1) In China, the genus Populus exhibited a zonal distribution that was in an east-west direction, which was wider than that in the north-south direction; (2) The greatest species diversity of the Populus distribution on the latitudinal and longitude gradient was located in the latitudinal and longitudinal bands of 30-40°N and 110-120°E, respectively, indicating that species richness was the greatest where the longitude and latitude were optimized and decreased as the longitude and latitude moved above or below the optimal range; (3) The distribution center of the Populus species biodiversity in China was located on both sides of the Heihe-Tengchong line in the northeast-southwest direction, and species diversity increased from the northeast to southwest of China along the line, but decreased from this line to the northwest and the southeast; (4) In terms of the level of taxonomy, the sections of Populus with the most extensive distribution range were sect. Populus and sect. Tacamahaca Spach in China and the four species with the most extensive distribution ranges were Populus davidiana Dode, Populus simonii Carr, Populus adenopoda Maxim, and Populus cathayana Rehd, which revealed that the differing levels of taxonomy within the same taxa resulted in a varied species diversity pattern on the same scale.