The membrane lipid peroxidation and protective enzyme activity in the annual seedlings of Acer ginnala Maxim and Acer mono Maxim were studied under lead stress through pot experiment. Treatments Pb100，Pb500，Pb1000，Pb2000 were added with 100, 500, 1 000 and 2 000 mg/kg of Pb(CH3COO)2•5H2O (pure Pb2+) respectively and the treatment with no Pb2+ addition was served as control(CK). Indexes of the leaf samples were determined 75 d after Pb addition. The results showed that chlorophyll a/b and proline contents decreased while relative conductivity, manlondialdehyde (MDA) content and the activity of peroxidase (POD) increased with the increase of lead concentration in soil. The activity of superoxide dismutase (SOD) rose firstly and then went down. The variations of these indexes in Acer mono were greater than those in Acer ginnala. Lead stress caused membrane lipid peroxidation in the plants and the peroxidation increased with increasing intensity of lead stress, which meanwhile caused anti-peroxidation effect. SOD played an important role and the change of POD was not obvious during the process of removing peroxidation products. In general, both Acer ginnala Maxim and Acer mono Maxim were tolerant to lead stress and the former had greater tolerance than the latter. Two kinds of trees could be used as landscape trees in lead polluted area.