Abstract: The growth, development and ingestion of the Pseudodiaptomus annandalei were investigated by using Platymonas subcordiformis with different phosphorus contents as food. The growth rates of Pseudodiaptomus annan-dalei were (0.04370.0030)/d and (0.03390.0049)/d when using Platymonas subcordiformis with low P content (C/P=197 or 375 in molar) as food. The growth rate was (0.10400.0395)/d when using Platymonas subcordiformis with high P content (C/P=78 in molar) as food. Furthermore, the period of naupliar stage under low P condition was pro-longed by 1.52 times compared to those under the P-sufficiency condition. The P content was 0.30%0.33% of dry weight in the animals under P-sufficiency condition, while it decreased to 0.08%0.28% in the low P condition. There was a close linear significant correlation between the growth rates and P contents in the copepodite. The ingestion rates of nauplius, copepodites and adults decreased significantly in low P condition compared with those under P-sufficiency, which changed from790, 720 and 728 cells/(ind?h) in the P-sufficiency condition to 150370, 695703 and 648733 cells/(ind?h) in the low P condition, respectively. It was concluded that the nutritional quality (C/P and C/N ratio) of algae was degraded in low P condition, which led to the significant impairment on the growth and ingestion of the Pseudodiaptomus annandalei. Therefore, the P-limitation in marine copepods was verified.