Abstract: The response surface method was used to study the steam softening of teak plantation with ammonia compounding alkali liquor, and the effects of wood weight gain rate, hydrothermal temperature and hydrothermal time on the bending performance of wood were analyzed. The results showed that bending property of the teak plantation can be significantly increased by the ammonia compounding alkali liquor. The optimal conditions contained: 37 % weight gain rate, 115 ℃ hydrothermal temperature and 5.8 h hydrothermal time. The measured bending performance has an h/r value of 0.082. It is concluded that ammonia compounding alkali liquor can be applied to the bending of teak plantation.