Abstrct Single factor test was used to study the effects of four different types of phosphorus on growth of Prorocentrum donghaiense,NaNO₃ was the sole nitrogen source,the initial nitrogen concentration was 40μmol·L^-1,and the six original phosphorus concentrations was setup as the following:0.1μmol·L^-1、0.5μmol·L^-1、1.0μmol·L^-1、2.0μmol·L^-1、5.0μmol·L^-1、10.0μmol·L^-1.The four different types of phosphorus were:NaH₂PO₄(Sodium dihydrogen phosphate),ATP(Adenosine disodium triphosphate),G-6-P(D-glucose-6-phosphate,sodium salt) and G-P(Sodium glyceroophosphate);The results showed that all four types of phosphorus can be utilized by P.donghaiense.When using G-6-P,ATP and NaH₂PO₄ respectively as the phosphorus source,the maximum Specific growth rate(μ_max) and the maximum biomass of P.donghaiense were similar;but when using G-P as the phosphorus source,the maximum Specific growth rate(μ_max) and the maximum biomass of P.donghaiense were the lowest.The results further suggest that dissolved organic phosphorus(DOP) in the nature seawater with the similar structure as the former three organic phosphorus can act as the alterative phosphorus source of the outbreak and maintaining of the red tide of Prorocentrum donghaiense.