Abstract: To investigate the effects of temperature, irradiance level and nutritional history of nitrogen or phosphorus on inorganic phosphorus uptake in Hizikia fusiforme, we cultivated thalli under different conditions , measured the concentration of inorganic phosphorus in media at 0, 0.5th, 1st, 2nd, 4th, 6th and 9th hour, and determined the uptake rate. We set the temperature at 10 ℃, 20 ℃ and 30 ℃, and irradiance levels at 0, 1 500 lx and 6 500 lx in different experiments respectively. Different nutritional histories were obtained by growing thalli at different concentrations of nutrient for 96 h, including 3 levels ofphosphorus (0, 5 molL-1and 50 molL-1) and 3 levels of nitrogen(0, 10 molL-1 and 200 molL-1), respectively. The results show that the uptake rate of inorganic phosphorus reaches maximum at 20 ℃, while the minimum at 10 ℃. With the enhancement of irradiance level, uptake rate increases. Thalli with nutritional history of lower phosphorus concentration show a higher uptake rate of phosphorus, and vice versa. For different nitrogen histories, higher uptake rate is found in alga with higher nitrogen history, and there is no significant difference between 0 and 10 molL-1 nitrogen histories.