Laboratory culture experiments showed that < 100μmol/L nitrate, amonium or mixture of aminoacids promote the growth of the red tide organism Prorocentrum micans Ehrenb, but that >100μmol/Lof ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphatewas P. micrns’main phosphorous soruce in the ocean. Presence of 80μmol/L EDTA, 0.5 to 1μmol/LFe~(3+), 1.0 to 20.0 μmol/L Mn~(2+) 0.1 to 0.4 μmol/L Co~(2+) in the culture medium could improvethe growth of P. micans. Vitamin B_1 promoted growth, but vitamin B_(12) and biotin did not. Theestimated minimum cell quotaS (q_ο) for nitrogen and phosphorus being 0.74 pmole/cell and 0.045pmole/cell show that phosphorus (more than nitrogen) limits the growth of P. micans in the study area. Laboratory culture experiments showed that <100 μmol / L nitrate, amonium or mixture of aminoacids promote the growth of the red tide organism Prorocentrum micans Ehrenb, but that> 100 μmol / L of ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphatewas Presence of 80 μmol / L EDTA, 0.5 to 1 μmol / L Fe 3+, 1.0 to 20.0 μmol / L Mn 2+ 0.1 to 0.4 μmol / L Co ~ ( 2+) in the culture medium could improve the growth of P. micans. Vitamin B 1 promoted growth but but vitamin B 12 (12) and biotin did not. Theestimated minimum cell quota S (q_ο) for nitrogen and phosphorus being 0.74 pmole / cell and 0.045 pmole / cell show that phosphorus (more than nitrogen) limits the growth of P. micans in the study area.