Abstract: In order to investigate differential response of trehalose metabolism to drought and low temperature stress, and roles of trehalose in the forming of drought and chilling resistance, tobacco seedlings（cv. Yunyan 203）were treated under drought and low temperature stresses. Then the changes of trehalose content, their activities of enzymes related to metabolism（TPS, TPP and THase）and gene expression were detected in the tobacco leaves during the drought and chilling stress at 4℃. The results indicated that trehalose content increased firstly, achieved the maximum level in 2 d, and the trehalose content in the leaves under drought stress always maintained higher level than that under the chilling stress. Similar to the change pattern of trehalose content, TPS, TPP activities were increased firstly and then decreased, and showed higher under the drought stress. On the other hand, THase activity demonstrated persistent increase under the drought and chilling stress, and was higher under chilling stress than that under drought stress. The expression level of TPS, TPP, and THase genes was higher in the drought stress than the control at 0 d, but the expression level under chilling stress was lower than the control. Above results showed that drought and chilling stress induced the accumulation of trehalose, the drought stress led to relatively higher level of trehalose content, related enzyme activities and gene expression, implying that response of trehalose to drought stress was more sensitive than that to chilling stress.