Abstract: Nanjing 49 was used in the experimentation to determine the effect of seedling planting density on the canopy and yield of the super-rice.The results showed that Nanjing 49's adaptability to the varying planting density was rather broad.It could reach a high yield at the range of 2-4plans·hill-1.However, when the planting density was more than 5plants·hill-1, the productivity significantly reduced.It appeared that Nanjing 49 adapted to the varied planting density by different means.For example, at the rate of 2plants·hill-1, it increased the total dry matters to reach a high yield by increasing its tillers per plant, total grains per spike, and photosynthetic capacity per leaf.At 3plants·hill-1, a high yield was achieved through increasing the total leaf area and effective panicles per hill.Then, when the planting was increased to 4plants·hill-1, it improved the yield by increasing LAI and reducing the leaf's base angle of the second leaves to effectively increase the sunlight reception.Therefore, with its high adaptability to the planting density, Nanjing 49 could provide a yield as high as (12.63±0.253) t·hm-2 on a reduced number of seedlings·hill-1 (e.g., 2plants·hill-1) to save on the planting cost.