Changes in aboveground dry matter (DM), leaf area index (LAI), photosynthetically active radiation (PAR), solar energy utilization efficiency, and configuration of plant were investigated in field experiment during the growing seasons of summer soybean (Glycine max cv. Ludou 4) in 2006 and 2007. The summer soybean experiment consists of 5 planting patterns under the same plant population density (3.09×105 plant/hm2). Row spacing (cm)×plant spacing (cm) was 18 cm×18 cm (A), 27 cm×12 cm (B), 36 cm×9 cm (C), 45 cm×7.2 cm (D), and 54 cm 6 cm (E), respectively. The differences in dry matter weight under different plant-row spacing were observed. The DM of all treatments reached maximum at 70 days after sowing (DAS) and 100 DAS, however, the DM of A treatment was 21.6% and 34.0% higher than that of E treatment at 80 DAS and 100 DAS, respectively. Accumulative priority of DM at different portions of the whole plant increased with widening of row spacing. The LAI of all treatments decreased with row spacing widened, and that of A and B treatment had higher value and longer time than the others. The solar energy utilization efficiency of different treatments generally increased with row spacing increased. For different plant-row spacing of the summer soybean population, number of grain per plant and 100 grain weight were positively correlated with yield, and correlation coefficients were 0.941* and 0.926* (in 2006), 0.995*and 0.892* (in 2007), respectively. PAR transmittance rate decreased, interception rate and solar energy utilization efficiency increased with a narrowing in row spacing, and thus yield increased. The yields of A and B treatments were significantly higher than that of E treatment (P＜0.05). The summer soybean population of relatively uniform distribution improves population structure, and increases the PAR interception, solar energy utilization efficiency and yield under rainfed agriculture.