Abstract: Taking 85 japonica rice varieties as experimental materials, the photosynthetic matter production indices such as leaf area index, SPAD value, photosynthetic potential, net assimilation rate,specific leaf weights and light energy utilization efficiency of japonica rice at different yield levels were compared and studied, so as to provide theoretical basis for high yield cultivation of japonica rice and breeding of excellent varieties. The results showed that the leaf area index at the heading stage, SPAD value of upper three leaves, photosynthetic potential and net assimilation rate during the heading to the maturity stage, and light energy utilization efficiency of japonica rice varieties with different yield levels increased gradually with the increase of yield level, and the proportion of stem-sheath and leaf nitrogen distribution at the maturity stage decreased gradually with the increase of yield level, and the difference among yield levels was extremely significant. Correlation analysis showed that the effects of photosynthetic potential and net assimilation rate during the heading to the maturity stages on yield were extremely significantly different（r≥0.75**）, followed by light energy utilization efficiency（r=0.68**）. At the same time, leaf area index at the heading stage and SPAD value of upper three leaves were extremely significant positive correlated with light energy utilization efficiency; effect of SPAD value of flag leaf on light energy utilization efficiency at 20 days after the heading was higher than that of the top second and the third leaves; the proportion of grain nitrogen distribution at the maturity stage was significantly positive correlated with specific leaf weight and light energy utilization efficiency, and very significantly positive correlated with nitrogen photosynthetic efficiency at the heading stage. Therefore, a high level of leaf area index at the heading stage and SPAD value of flag leaf after the heading were conducive to improve the photosynthetic production capacity after the heading and the proportion of grain nitrogen distribution at the maturity stage, so as to promote the production of photosynthetic substances and improve the utilization rate of light energy, which was an important reason for high yield of japonica rice.