Waterlogging strongly affects agronomic performance of maize (Zea mays L.). In order to investigate the suitable selection criteria of waterflooding tolerant genotypes,and identify the most susceptible stage and the best continuous treatment time to waterlogging,20 common maize inbred lines were subjected to successive artificial waterflooding at seedling stage,and waterlogging tolerance coefficient (WTC) was used to screen waterflooding tolerant genotypes. In addition,peroxidase (POD) activities and malondialdehyde (MDA) contents were measured for 6 of 20 lines. The results showed that the second leaf stage (V2) was the most susceptible stage,and 6 d after waterflooding was the best continuous treatment time. Dry weight (DW) of both shoots and roots of all lines were significantly reduced at 6 d time-point of waterlogging,compared to control. POD activities and MDA contents were negatively and significantly correlated,and the correlation coefficient was -0.9686 (P