Abstract: The influence of different phosphorus concentrations (0.02, 0.10, 0.50, 8.00 and 16.00 mmol/L) on the growth and physiological traits of two hemp cultivars (Yunma 7 and Bamahuoma) were studied through hydroponic culture. The results showed that the optimum phosphorus concentration of Yunma 7 was 0.50 mmol/L while Bamahuoma was 8.00 mmol/L. The phosphorus tolerance of the two cultivars showed significant difference. Phosphorus stress limited the hemp growth or even led to death in the higher or lower phosphorus concentrations. Compared to the optimum phosphorus concentration, the plant height, stem diameter, and fresh weight significantly decreased both by increasing or decreasing-phosphorus concentration. However, the relative electrical conductivity, MDA content, and the activity of POD in hemp leaves increased. In addition, the root/shoot ratio and the activity of Apase decreased with the increase of phosphorus concentration from 0.02 to 16.00 mmol/L. The results might serve as the foundation for exploring of the effect of phosphorus on industrial hemp and for the breeding of hemp cultivars with high phosphorus efficiency.