Abstract: In order to study the gender differences of male and female individuals' adaptability to natural slope position, the secondary Broussonetia papyrifera population in the degraded slope lawn of purple hilly area was used as study materials. The slope was divided into four slope positions as uphill, middle, downhill and flat, and population characteristics such as population area, population density, age structure, male-female ratio, distribution coefficient, and other characteristic parameters, as well as the height and ground diameter of male and female individuals were determined. The results showed that: (1) There were significant differences in slope size and soil physical and chemical properties among the 4 slope positions (P<0.05). B. papyrifera could invade each position and form secondary population, but the population area and density increased exponentially with the decrease of slope position (P<0.05). (2) The slope position significantly influenced the age structure of the population. With the decrease of the slope position, the proportion of one-year seedlings increased, while the proportion of young trees and adult trees decreased (P<0.05). The age structure of B. papyrifera population on uphill and middle slope was declining type, the downhill was stable and the flat was increasing type. (3) The slope position significantly affected the sex ratio of young trees and adult trees, with male plants on the uphill and middle slopes, and female plants on the downhill and flat slopes. (4) The slope position significantly affected the age spatial distribution pattern of B. papyrifera. The lower the slope position, the more annual seedlings and seedling trees were clustered. With the increase of tree age, the distribution coefficient decreased, and the females tended to be evenly distributed, while the males tended to be randomly distributed. (5) The slope position had more influence on the height of different trees than the ground diameter. The plant height increased with the decrease of slope position, while the ground diameter increased with the increase of soil thickness. To sum up, B. papyrifera invaded the degraded lawn and formed a mixed community of B. papyrifera and herbs. The males' tolerance to the lack of resources was better than females, and the females' competitiveness to resources was stronger than males. The secondary population characteristics and individual growth strategy matched with the slope position and soil physical and chemical properties, so B. papyrifera was suitable for popularization and application in vegetation restoration of bare slope.