The changes of reactive oxygen species, antioxidant enzyme activity, and antioxidant substance contents in roots and leaves of Pugionium cornutum (L.) Gaertn. and P. dolabratum Maxim. were measured with potculture drought stress in greenhouse, and the drought resistance of them were evaluated by the method of membership function and drought resistance coefficient. The results showed that: (1) with the increase of drought stress, the O^-·₂ generation rate and the contents of ·OH, H₂O₂ and MDA increased in roots and leaves of P. cornutum and P. dolabratum. Moreover, P. cornutum produced more ROS and MDA than that of P. dolabratum under drought stress. (2) With the increase of drought stress, the activities of POD, APX and GST increased firstly and then decreased, the activity of CAT increased in roots and leaves; The activity of SOD in leaves, GR and GPX in roots decreased firstly and then increased, the activity of GR in leaves increased firstly and then decreased, but the activity of GPX in leaves, SOD in roots increased; The activities of SOD, POD and CAT in roots and leaves of P. dolabratum were higher than that in P. cornutum. (3) The content of AsA increased firstly and then decreased, the content of GSH increased, and the content of CAR decreased in roots and leaves; The content of VE in leaves increased, the content of VE in roots decreased; P. dolabratum made more AsA and GSH, the AsAGSH cycle system in P. dolabratum could remove more ROS than that in P. cornutum. (4) The TAOC (total antioxidant capacity) increased in roots and leaves; The antioxidant ability of P. dolabratum was higher than that of P. cornutum. We know that drought resistance of P. cornutum were higher than that of P. dolabratum under light drought stress. However, drought resistance of P. dolabratum was higher than that of P. cornutum under moderate and severe drought stress by comprehensive drought resistance coefficient and average subordinate function of reactive oxygen species scavenging system indexes in response to drought stress of two species in Pugionium Gaertn. Under drought stress, the ROS and MDA contents in P. dolabratum were lower than those in P. cornutum, and the most of antioxidant enzyme activities and antioxidant contents in P. dolabratum were higher than those in P. cornutum. The reactive oxygen species scavenging system showed stronger drought resistance in P. dolabratum than those in P. cornutum.