Abstract: Under low and high P application, 6 Maize genotypes were selected to compare the biological characteristics and P efficiency by hydroponic culture and pot experiment in maize genotypes. The main results were summarized as follows: The relative length of chief root (RLC) and relative root-shoot rati(RRR) were low in hydroponic culture than pot experiment , but relative dry weight(RW) and P efficiency were high. The variance analysis indicated that the difference of length of chief root, root-shoot ratio, relative dry weight and P efficiency was significance between hydroponic culture and pot experiment.