We used eight months of oil palm seedlings as materials to study the effect of different time of low temperature stress on physiological and biochemical changes of oil palm seedling, and according to the temperature variation in Hainan, set up four different minimum temperature treatments including CK(natural temperature treatment), 18℃(T1 treatment), 12℃(T2 treatment) and 6℃(T3 treatment) after 0, 7, 14, 21 d sampling, respectively. With the decreasing of temperature and the increasing of time, the oil palm seedling leaf water content and SOD activity continued to decrease, the soluble protein, sugar content, H₂O₂ and MDA content continued to increase, and POD, CAT, APX activity first increased and then decreased. Under T2, T3 the seedling leaf became brown and oil palm seedling growth slowed down significantly after twoweek treatment. Low temperature caused obviously oxidative damage, but oil palm seedlings used adaptation mechanisms by increasing the contents of soluble protein, sugar and antioxidant enzyme activity to resist oxidative damage caused by low temperature for normal growth.