to N or P deficiency, and its compensatory growth under normal nutrient conditions (f/2 culture media) were studied. Two experimental treatments that included a nutrient deficiency period and a period without nutrient stress, were conducted. First, was cultured for 10 days under nutrient stress that included, poor nutrients, N deficiency, P deficiency, and N plus P deficiency, while normal nutrient conditions (f/2 culture media) served as a control. Second, nutrient stress was removed, and the treated and control groups were cultured for another ten days at the same inoculation density and a sufficient nutrient supply, simultaneously. Cell density, growth rate, relative growth rate, generation time and Chlorophyll-a was determined during the two periods. The results indicated that nutrient stress has an inhibitory effect on cell growth. Phosphorus deficiency had the least inhibitory effect, whereas N plus P deficiency had a comparatively large inhibitory effect. There was a significant difference (<0.05) in the growth condition of algal cells between the treated and control groups. Maximum cell densities of the control, poor nutrients, N deficiency, P deficiency, and N plus P deficiency groups were 83×10⁴ cell·mL^–1, 32×10⁴ cell·mL^–1, 43×10⁴ cell·mL^–1, 78×10⁴ cell·mL^–1 and 29×10⁴ cell·mL^–1, respectively. Maximum , 0.54 d^–1and 0.51 d^–1; maximum average relative growth rates were 0.61 d^–1, ; minimum generation times were 1.13 d, 1.76 d, 1.58 d, 1.58 d and 2.00 d, and maximum chlorophyll-content a was 723.7 μg·μL^–1, 286.4 μg·μL^–1, 427.1 μg·μL^–1, 694.2 μg·μL^–1 and 292.9 μg·μL^–1, respectively. During the periods when nutrient stress was removed, it was found that after being subjected to nutrient stress, had the ability of compensatory growth, particularly in the P deficiency treatment. There was a significant difference (<0.05) in the growth condition of algal cells between the treated and the control groups. The main characteristic of compensatory growth of was that the treated group had a higher average relative growth rate, a greater number of cells, and higher chlorophyll-a content than the control group in the initial culture time. In addition, the maximal rate range of net cell increase was 0.30%–80.95%, and the generation time of the cells was shorter. As the culture time proceeded, the difference between the treated group and the control group decreased. Eventually, all parameters of the treated and control groups were similar. These results showed that has over-compensatory growth under conditions of nutrient stress, particularly during P deficiency. This might be the cause of harmful algal blooms in the China Seas, which are P deficient year-round.