Abstract: 【Objective】 Effects of functional leaves with different leaf positions on the formation of spike biomass in two habitats of Bosten Lake. 【Methods】 The reed population in bosten Lake, the largest reed producing area in China, was selected as the research object. Five traits of the top three leaves of Ph. australis in wetland and dry land were measured by field sampling method, including leaf length, leaf width, leaf area, leaf biomass and spike biomass. 【Results】 The reed weight in wetland was 2.1 times higher than that in dry land (P<0.05). There was a significant positive correlation between ear biomass and four leaf traits (P<0.05), and the correlation degree varied with different leaf positions. The correlation coefficient between ear biomass and top leaf area of Ph. australis in wetland was the largest (0.920,5), followed by that of top leaf biomass (0.723,7); the correlation coefficient between ear biomass and top three leaf area of Ph. australis in dry land was the largest (0.826,7), and followed by that of top two leaf area (0.801,4). 【Conclusion】 There is a significant correlation between leaf and panicle biomass in different leaf positions. Leaf area and leaf biomass are the key factors affecting panicle biomass. In wetland, the correlation between top leaf and panicle biomass is the highest, while in dry land, the correlation between top three leaf and panicle biomass is the highest.