The thermal behavior of a modified soy-based protein adhesive was characterized with differential scanning calorimetry（DSC） in this study.After its theoretical curing temperature range from the DSC was identified,the soy-based adhesive was used to manufacture poplar plywood（250 mm × 250 mm × 4mm） in the laboratory.An orthogonal method was used to design an experiment to investigate effects of the process parameters on plywood bonding performance.Optimal process parameters were the press pressure of 1.4 MPa,press temperature of 165 ℃,pressing time of 1.4 min/mm,and adhesive spread of 220 g/m2.The result showed that the bonding strength of the plywood,after accelerated aging test（4-hour boiling,20-hour drying,and 4-hour boiling）,exceeded the requirement of the Chinese National standard,GB/T 9846-2004,for type I general purpose plywood.