The growth rate, photosynthesis and chlorophyll fluorescence of Nostoc flagelliforme Born. et Flah. cultured under different medium were tested. The results showed that after 11 d cultivation, the content of chlorophyll a in different medium were 1.08 mg/L ( Detmer), 1.87 mg/L (Kratz-Myers), 1.21 mg/L (hydrophilous 104), and 2.18 mg/L (BG11), respectively. N. flagelliforme in BG11 had the fastest growth rate. Compared with other concentrations of BG11, the N. flagelliforme cultured in BG11 had the highest gross photosynthesis Pm (218.1 mu mol O-2 . mg(-1)chl a . h(-1)) and the highest ratio of chlorophyll fluorescence (Fv/Fm = 0.349). The results indicated that BG11 is optimal to cultivate N. flagelliforme and improves its activities of photosynthesis and chlorophyll fluorescence markedly.