近岸海域富营养化导致浮游藻类大量繁殖，影响海域生系统平衡。对湛江海域浮游藻类种类组成、数量分布、群落结构等进行冬、夏二季调查，得出湛江海域以硅藻门（Ｂａｃｉｌｌａｒｉｏ－ｐｈｙｔａ）为主要优势类群。夏季种类多样性高于冬季；赤潮生物种种类、数量均夏季高于冬季。 Eutrophication in coastal waters leads to large numbers of phytoplankton species that affect the balance of marine systems. The species composition, population distribution and community structure of planktonic algae in Zhanjiang sea area were investigated in winter and summer. The results showed that Bacillario-phyta was the dominant group in Zhanjiang sea area. Summer species diversity is higher than in winter; red tide species species, the number of summer are higher than in winter.