Abstract:Changes of soil's water content,dehydration of leaves,root's water content and activity of roots of the six wild flowers were studied in the easten section of Yanshan Mountain.The results showed that the tolerance of the species was in order of Securinega suffruticosa(Pall.) Rehd.>Euonymu phellomanus Loes.>Elaeagnuas multiflora Thunb.>Grewia biloba var.parviflora(Bge.) Hand.>Celastrus orbiculatus Thunb.>Myripnois dioica Bge.There was not necessary relationship between leaf abscission,the time when the wilting leaf appeared and the ability of drought-torance.Euonymu phellomanus Loes.and Elaeagnuas multiflora Thunb.were belonged to delay dehydration species that the time that the wilting leaf appeared were the latest;Securinega suffruticosa(Pall.) Rehd.and Grewia biloba var.parviflora(Bge.) Hand.were belonged to the species that endure drought stress by leaf abscission.The leaves' water content dramatically decreased and the time that the wilting leaf of them appeared were the earliest;The time that the wilting leaf of Celastrus orbiculatus Thunb.and Myripnois dioica Bge.appeared were between them and had the least ability of drought-torance.The root's water content gradually decreased with the drought stress.The trends of the ratio to free water of bound water and root activity were similar,they increased at first and then decreased and reach the minimizeat the dead point.The time appeared of increasing peak was different for the six plants and the peak was adapt to the drought stress.